OPINION

CALLAHAN, Circuit Judge:

In December 1988, Michael Apelt ("Apelt") and his brother, Rudi, murdered Apelt's wife of less than two months in order to collect on her life insurance policy. The brothers were tried separately, convicted of first degree murder, and given death sentences. Having obtained no relief in the Arizona courts, Apelt filed a habeas petition in the United States District Court for the District of Arizona. After a stay of proceedings to allow Apelt to advance a claim in the state courts based on the Supreme Court's decision in Atkins v. Virginia, 536 U.S. 304, 122 S.Ct. 2242, 153 L.Ed.2d 335 (2002), the district court granted the writ on one issue, ineffective assistance of counsel ("IAC") at sentencing, and denied relief on all of Apelt's other claims.

In No. 15-99013, the state of Arizona appeals, challenging the district court's jurisdiction to reach the merits of Apelt's IAC claim, as well as its grant of the writ. In No. 15-99015, Apelt appeals two claims certified by the district court: the denial in state court of funding to investigate mitigating evidence, and the determination that Apelt had failed to show that he was intellectually disabled under Atkins. In addition, Apelt raises two issues that were not certified by the district court: whether the Arizona Supreme Court applied an unconstitutional causal nexus requirement in reviewing Apelt's sentence; and whether trial counsel was ineffective in failing to challenge Apelt's competency to be tried and sentenced.

Apelt's habeas petition is subject to review under the Antiterrorism and Effective Death Penalty Act of 1996 ("AEDPA"), 28 U.S.C. § 2254(d). See Mann v. Ryan, 828 F.3d 1143, 1151 (9th Cir. 2016) (en banc). We first determine that federal court review was not procedurally barred. We then vacate the district court's grant of relief because we cannot find the Arizona Supreme Court's determination that Apelt's counsel's deficient performance at sentencing was not prejudicial to be clearly unreasonable. See Davis v. Ayala, ___ U.S. ___, 135 S.Ct. 2187, 2199, 192 L.Ed.2d 323 (2015); Cullen v. Pinholster, 563 U.S. 170, 189, 131 S.Ct. 1388, 179 L.Ed.2d 557 (2011). We affirm the district court's denial of relief on Apelt's claims of inadequate funding to investigate mitigating evidence, and mental disability pursuant to Atkins, 536 U.S. 304, 122 S.Ct. 2242. We grant the certificate of appealability for Apelt's claims of an application of an unconstitutional causal nexus standard by the Arizona Supreme Court and for ineffective assistance of counsel in failing to challenge Apelt's competency to stand trial, and we deny those claims on the merits.

I.

A. The Facts

Michael Apelt, the youngest of seven siblings, was born in August 1963 in Germany. He came to the United States in the late summer of 1988. The underlying facts leading to Apelt's conviction were fairly and fully set forth in the Arizona Supreme Court's opinion, State v. Apelt, 176 Ariz. 349, 861 P.2d 634 (Ariz. 1993), as follows:

861 P.2d at 638-42.

B. The Trial and Sentencing

Apelt was charged with first degree murder and conspiracy to commit first degree murder, and attorney Michael Villarreal was appointed to represent Apelt. Apelt was tried in April 1990, testified in his own defense, and was convicted of both murder and conspiracy to commit murder. Apelt, 861 P.2d 634.

A presentence hearing was set for August 7, 1990. On June 8, Villarreal filed a motion for travel funds for him to go to Germany to investigate possible mitigating evidence. He told the court:

The prosecutor interjected that perhaps it would be more efficient and economical to hire an investigator in Germany. Villarreal responded:

The trial judge commented that "this has been a very expensive case to this point in time, and I am concerned about when it is the defendant has the right to have all these things furnished to him at no cost." The judge noted that the costs had already exceeded $200,000.00. The court gave Villarreal a week to submit a statement, "a verification as to those items that you feel that your trip to Germany is a necessity for."

Villarreal did not submit such a statement. Instead, at the August 7, 1990 hearing, he sought a continuance and again argued that he needed to undertake an investigation in Germany.1 Arizona objected to a further continuance, arguing that the court had "indulged every whim of this defendant and his counsel in allowing him to present an adequate defense and fully investigate this case." The prosecutor further noted that Villarreal had provided some documents that he acquired through a German lawyer and through Amnesty International. Villarreal denied that either the attorney or Amnesty International had been of any help.2

The trial court denied Villarreal's motion to continue, and proceeded with the presentencing hearing. The prosecutor indicated that she would rely on the testimony presented during the course of the trial and asserted three aggravating circumstances: (1) Apelt committed the crime for pecuniary gain; (2) the crime was heinous, cruel and depraved; and (3) Apelt procured the assistance of another by promise of payment.

The court then asked Villarreal for whatever evidence he would proffer in mitigation. He offered eight exhibits that he had received the day before through fax and overnight mail.3 After receiving the exhibits, which had just been translated into English the night before, the court took a recess to allow the prosecutor to review the documents.

After the recess, the prosecution called Detective Ronald Davis as a rebuttal witness. Davis spoke German, had been involved in the investigation of Cindy's murder, and had traveled to Germany to investigate Apelt. He testified that he spent an entire day with the Dusseldorf police who did not show him Apelt's criminal record, but read the record to Davis.

Villarreal objected to Davis' testimony as unsubstantiated hearsay. The prosecutor responded that the letters submitted by Villarreal were in the nature of character references and Arizona was entitled to rebut them. The judge initially was dubious of Arizona's position, but was persuaded by Arizona's argument that the testimony was relevant to whether the life sentence for conspiracy should run consecutively or concurrently with the death penalty.

Davis then testified that Apelt had a felony conviction and that Apelt's former wife told him that Apelt had "been involved in some sort of attack involving a knife with a homosexual partner." Davis reported that the former wife also stated that Apelt was quite capable of committing murder for money, and had asked her to donate one of her kidneys in order for him to get money.

In her summation, the prosecutor, after noting the three aggravating factors, argued that there were no mitigating factors. She argued:

In response, Villarreal first questioned whether there was really evidence of intent for financial gain or that the crime was particularly cruel, heinous, and depraved. He then offered the following arguments in mitigation: (1) Apelt was only 25 years old at the time of the crime; (2) there is remorse; (3) he cooperated in the pre-sentence report; (4) Apelt has recently found Christ; (5) there is a lack of a prior record of any serious crime; (6) Apelt has an honorable military discharge; (7) Apelt displayed good behavior at trial; (8) Germany has a strong position against the death penalty; and (9) some of the victims favored a life sentence.4 Villarreal also mentioned some of the areas of mitigation that he had not been able to pursue, such as Apelt's capacity to appreciate wrongfulness of conduct, reports of "hospitalization in a clinic, some type of psychiatric clinic, emotional disturbance clinic of some sort in Germany," and possible low intelligence and lack of education. But, because he could not travel to Germany, he was not able to obtain such information.

On April 13, 1990, the trial judge imposed the death sentence. Villarreal continued to represent Apelt on his direct appeal.

C. Initial Post-Conviction Proceedings

Rudi was tried the week after Apelt and was sentenced and convicted of first degree murder. On May 28, 1991, Villarreal filed a post-conviction petition on behalf of Apelt. The petition was based on the testimony of a Dr. DiMaio in Rudi's trial. The petition asserted:

The Superior Court of Pinal County denied the petition on May 28, 1991. The Arizona Supreme Court then consolidated the denial of the first post-conviction petition with Apelt's direct appeal.

The Arizona Supreme Court affirmed Apelt's conviction and sentence, rejecting a host of arguments advanced by Villarreal. Apelt, 861 P.2d 634. Of greatest concern in this federal habeas proceeding is the court's treatment of Apelt's challenges to his sentence. The court characterized the first challenge as whether "the trial court err[ed] by refusing to fund a trip to Germany so defense counsel could look for mitigating evidence." Id. at 642. The court determined that there was no error because a defendant must demonstrate how the requested assistance would be beneficial and why it is necessary for a fair trial, and Apelt had failed to make such a showing. Id. at 651. The court noted that Villarreal failed to file a statement showing why the proposed trip to Germany was necessary, and that the adequacy of a showing is left to the discretion of the trial judge. Id. The court commented that counsel did not explain why psychological hospitalization might be mitigating, or "why a difficult childhood and lack of education would be mitigating."5 Id. It concluded that because Apelt "failed to show that helpful evidence was available in Germany," he had no right to funding under the statute or the due process clause of the Fourteenth Amendment. Id. at 652.

The Arizona Supreme Court addressed two questions concerning the appropriateness of the death sentence: (1) did the court err in finding three aggravating factors; and (2) did the court err in "finding that there were no mitigating factors sufficient to outweigh the aggravating factors." Id. at 642. The court found that there was more than sufficient evidence to support each of the three aggravating elements. Id. at 652-53. It also found that the trial court had considered the "mitigating" factors proffered by counsel and had not imposed an impermissibly high burden or failed to weigh the factors properly. Id. at 653. It independently reviewed the record and found three aggravating and no mitigating factors.6 Id. at 654.

As to the post-conviction petition, the court rejected Apelt's request for an evidentiary hearing, finding that Dr. DiMaio's testimony would not have changed the outcome of the trial because it made no difference whether Apelt or Rudi wielded the murder weapon. Id.

D. Apelt's Second Post-Conviction Proceedings

On December 4, 1995, Apelt, now represented by new counsel, filed an "amended petition for post-conviction relief" in the Superior Court for the County of Pina (the amended petition is generally referred to as the "PCR"). The PCR raised ten issues, including assertions that Apelt was denied effective assistance of counsel during the penalty phase of his case, on direct appeal, and on his first postconviction petition. Many of the assertions were based on newly discovered materials. The federal district court described the materials as follows:

Attached to the PCR was an affidavit from attorney Villarreal.7 He stated that: (a) he "did not hire an investigator in Germany to investigate any mitigation"; (b) he "did not file a supplementary statement at the court's request following the denial of funds by the court for the trip to Germany"; (c) "[a]ny lack of investigation or preparation during the penalty phase of this case was not a tactical or strategic decision"; (d) "Mr. Apelt did not take an active role in the development of mitigation"; and (e) he "did not withhold any objections, claims or defenses in order to gain a tactical or strategic advantage."

On January 23, 1996, Apelt filed a supplement to the PCR asserting that he was entitled to an evidentiary hearing (a) pursuant to Ake v. Oklahoma, 470 U.S. 68, 105 S.Ct. 1087, 84 L.Ed.2d 53 (1985), concerning his constitutional right to state-funded expert assistance, and (b) on whether his trial counsel was ineffective in failing to thoroughly investigate material aspects of his case.

Arizona filed a comprehensive response to the PCR, setting forth a detailed account of Apelt's actions leading up to the murder. It then argued that most of Apelt's claims, including his IAC claims, are precluded under Arizona Rule of Criminal Procedure 32.2, which, in essence, provides that a defendant may not raise an issue that was not raised but could have been raised "at trial, on appeal, or in any previous collateral proceeding. The response also asserted that although Apelt's claim of IAC by appellate counsel was not precluded, Apelt had not alleged any specific misdeeds that would overcome the deference due to counsel. The response also denied that Apelt had alleged any colorable claim of newly discovered material evidence.8 The evidence concerning Apelt's background could not be newly discovered because it was within Apelt's personal knowledge and was not diligently presented. Arizona further argued that Apelt cannot tie the evidence "to his cold-blooded commission of the murder, and none is `positive' character mitigation — at most it seeks some sort of pity or sympathy, which [Apelt] is not entitled to have considered in mitigation." The response also argued that there is no possibility that the alleged newly discovered evidence would have changed Apelt's sentence because Apelt exaggerates what is actually in the documents.

Arizona also argued in the alternative that Apelt's claims of IAC were meritless. Arizona asserted that, under Strickland, there is a strong presumption that counsel exercised reasonable professional judgment. Focusing on counsel's performance at sentencing, Arizona first noted that Villarreal asked for funds to go to Germany but did not file a verified statement as requested by the trial court. The State argued that Villarreal did all he could, given the lack of any mitigation in Apelt's background. It argued that Apelt and his attorneys "have had more than 5 years to cherry-pick through [Apelt's] past and dredge up mitigation, yet have failed to present anything that would arguably warrant a sentence less than death."

On September 4, 1996, the Arizona Superior Court for Pinal County denied Apelt's PCR. It held that most of the claims were precluded under Arizona's Rules of Criminal Procedure either because they had been adjudicated on direct appeal or because they were not raised at trial, on appeal, or in Apelt's first post-conviction petition. This included most of Apelt's IAC contentions, except his claim of IAC in his first post-conviction petition, which the court held was not cognizable in the proceeding. Two of the court's final three paragraphs are particularly relevant. The court held:

Apelt filed a petition for review to the Arizona Supreme Court, which summarily denied review on April 23, 1998.

E. Initial Proceedings in the District Court for Arizona

Apelt filed his federal habeas petition in the United States District Court for the District of Arizona in May 1998. However, before the district court could resolve the petition, the Supreme Court decided Atkins, 536 U.S. 304, 122 S.Ct. 2242, holding that the Eighth Amendment prohibits the execution of intellectually disabled persons.9 Based on the possibility that Atkins applied to Apelt, the district court stayed Apelt's sentencing-related claims to permit him to return to state court and exhaust his Atkins claim. In the meantime, the district court considered and denied Apelt's conviction-related claims.

F. The Atkins Proceedings in State Court

The superior court conducted an evidentiary hearing regarding the Atkins claims by both Apelt and his brother, Rudi, in April and May 2007. The superior court applied A.R.S. § 13-753(K)(3), which, at that time, defined intellectual disability as "a condition based on a mental deficit that involves significant subaverage general intellectual functioning, existing concurrently with significant impairment in adaptive behavior, where onset of the foregoing conditions occurred before the defendant reached the age of eighteen." The superior court found that Apelt met none of the criteria:

As to the second criterion, adaptive behavior, the court rejected the assessment of Apelt's expert, Dr. Ruff, as focused more on Apelt's maladaptive behavior rather than his ability to perform daily tasks. Reviewing Apelt's adulthood, the court noted that Apelt "has consistently displayed the ability to engage in independent and self-directed thinking, planning and conduct." The court commented that Apelt had "worked at various jobs, at least one for an extended time, served in the military and was honorably discharged, married, and lived independently." It further observed that Apelt had traveled to the United States and Mexico, and had learned English "sufficiently to communicate and interact appropriately with others, negotiated purchases of vehicles and apartment leases, understood foreign currency exchange rates, and obtained employment." The court concluded that Apelt "ha[d] not proved by even a preponderance of the evidence that throughout his childhood and adult life he has suffered from significant impairment in adaptive behavior in meeting the standards of personal independence and social responsibility expected of a person of his age and cultural group."

Finally, the superior court concluded that Apelt had failed to prove by even a preponderance of the evidence the onset of subaverage intelligence prior to reaching the age of eighteen.

In contrast, the superior court found that Rudi was intellectually disabled and vacated his death sentence. Rudi's IQ was lower than Apelt's IQ with test results ranging from 49 to 61. The court also found that Rudi exhibited developmental disabilities from an early age, had been "unable to attain gainful employment or function on his own," had been dismissed from military service after serving for less than a year, had never lived alone, and depended on Apelt to take care of him.

G. The District Court's September 1, 2015 Order

Following the superior court's denial of Apelt's petition for post-conviction relief based on Atkins, Apelt was allowed to amend his federal habeas petition to raise an Atkins claim. On September 1, 2015, the district court issued its order granting Apelt relief on one issue and otherwise rejecting his claims. The district court addressed the issues relevant to this appeal in the following order.

1. Procedural Status of Claims

The district court recognized that a state prisoner must exhaust his remedies in state court before filing a federal habeas petition, and that, when a claim is procedurally defaulted under state law, a federal court usually cannot reach the merits of the claim. It reasoned that before 2012, a procedural default would be excused only if the petitioner demonstrated both cause and prejudice, but that Martinez v. Ryan, 566 U.S. 1, 132 S.Ct. 1309, 182 L.Ed.2d 272 (2012), set forth a new standard. Citing our opinion in Cook v. Ryan, 688 F.3d 598, 607 (9th Cir. 2012), the district court held that now a petitioner may overcome a procedural default "by demonstrating two things: (1) `counsel in the initial-review collateral proceeding, where the claim should have been raised, was ineffective under the standards of Strickland ...' and (2) `the underlying ineffective-assistance-of-trial-counsel claim is a substantial one, which is to say that the prisoner must demonstrate that the claim has some merit.'"

Apelt asserted that his claims for IAC at sentencing (Claim 12), for failure to challenge his competency to stand trial (Claim 1-B), and for failure to challenge his competency at sentencing (Claim 1-D), are excused under Martinez by Villarreal's ineffective performance on his first postconviction petition. Arizona made a two-fold response. It argued that these claims were procedurally defaulted, but it also argued that if the court were to find Martinez applicable, the court would have to consider that the state court also denied the claims on their merits. Accordingly, if the court reached the merits, it should give deference to the state court's ruling and not review the IAC claims de novo. The district court agreed that it had to "accept that the two claims were resolved by the state court on their merits and review their rejection under the deferential standard applicable to Apelt's other claims."10

2. Claim 12 — IAC at Sentencing

The district court recognized that Apelt's IAC claim was governed by AEDPA and thus relief was only available if the state court's decision was an unreasonable application of clearly established Federal law or an unreasonable determination of the facts. See 28 U.S.C. § 2254(d). The court acknowledged that relief was precluded as long as "`fairminded jurists could disagree' on the correctness of the state court's decision," Harrington v. Richter, 562 U.S. 86, 101, 131 S.Ct. 770, 178 L.Ed.2d 624 (2011), and that review was "limited to the record that was before the state court that adjudicated the claim on its merits." Cullen v. Pinholster, 563 U.S. 170, 181, 131 S.Ct. 1388, 179 L.Ed.2d 557 (2011). Accordingly, the record could be expanded only once a petitioner showed that there was no reasonable basis for the state court denial of relief.

As Apelt alleged that Villarreal was ineffective because he failed to present classic mitigating evidence about his background and mental health, the district court stated that it had to determine "whether there is any reasonable argument that Villareal's performance at sentencing met the wellestablished constitutional minimum for effective assistance of counsel."

The district court recognized that, under AEDPA, the Strickland standard was "doubly deferential." Knowles v. Mirzayance, 556 U.S. 111, 123, 129 S.Ct. 1411, 173 L.Ed.2d 251 (2009). Quoting Richter, 562 U.S. at 105, 131 S.Ct. 770, the district court stated that "the question is not whether [Villarreal's] actions were reasonable. The question is whether there is any reasonable argument that [Villarreal] satisfied Strickland's deferential standard." The court further held that only the evidence presented to the state court would be considered.11

Turning to the substantive law, the district court stated that, in a capital case, counsel has an obligation to conduct a thorough investigation of the defendant's background. Williams v. Taylor, 529 U.S. 362, 396, 120 S.Ct. 1495, 146 L.Ed.2d 389 (2000). The court commented that although the exact contours of the obligation will vary, counsel "should obtain readily available documentary evidence such as school, employment, and medical records, and obtain information about the defendant's character and background" (Robinson v. Schriro, 595 F.3d 1086, 1108-09 (9th Cir. 2010)); should make "inquiries into social background and evidence of family abuse" (Summerlin v. Schriro, 427 F.3d 623, 630 (9th Cir. 2005)); and should review such evidence of mental impairment as might be found in mental health records (Lambright v. Schriro, 490 F.3d 1103, 1117 (9th Cir. 2007) (per curiam)). The court further noted that while an investigation typically begins with the defendant's interview, it cannot end there unless the "defendant has given counsel reason to believe that pursuing certain investigations would be fruitless or even harmful." Robinson, 595 F.3d at 1109 (quoting Strickland, 466 U.S. at 691, 104 S.Ct. 2052).

The district court concluded:

The district court explained that, in reaching its conclusion, it had taken into consideration Villarreal's statement that Apelt did not actively participate in the sentencing phase of trial. It found, however, that Apelt's lack of cooperation did not eliminate Villarreal's duty to investigate. See Hamilton v. Ayers, 583 F.3d 1100, 1118 (9th Cir. 2009); and Landrigan v. Schriro, 441 F.3d 638 (9th Cir. 2006) (en banc), rev'd, 550 U.S. 465, 127 S.Ct. 1933, 167 L.Ed.2d 836 (2007).

The court acknowledged that Villarreal's investigation was hampered by the need to obtain funding to travel to Germany, but concluded that his performance was nevertheless legally deficient. He failed to provide additional information to the trial court, as invited by the court, and offered no explanation for his failure. The court further noted that "[i]t is telling that PCR counsel obtained voluminous material regarding mitigation without traveling to Germany."

The district court also rejected Arizona's suggestion that Villarreal's conduct may have been strategic. It cited Wiggins v. Smith, 539 U.S. 510, 527, 123 S.Ct. 2527, 156 L.Ed.2d 471 (2003), and noted that, because Villarreal "intended to seek information about Apelt's mental health, including his hospitalization in Germany, ... he knew it was material evidence and, inexplicably, failed to pursue it." The court added that Villarreal "failed to present evidence of Apelt's childhood poverty and abuse — humanizing information that would have been within the parameters of good character evidence," and that Villarreal admitted that there was "no strategic basis for his failure to investigate or present more relevant mitigating evidence." The district court concluded that "[n]o fairminded jurist could conclude Villareal's performance was sufficient."

The court also found that the deficient performance was prejudicial: there was a reasonable probability that the result of the proceeding would have been different absent Villarreal's deficient performance. See Strickland, 466 U.S. at 694, 104 S.Ct. 2052. Villarreal's "case in mitigation contained no evidence of Apelt's alleged poverty, no evidence of childhood physical abuse, no evidence of repeated childhood sexual abuse, and no meaningful evidence of mental health problems." Indeed, the prosecutor stressed that Apelt had a normal childhood, and Villarreal submitted a statement from Apelt's mother that he had had a normal childhood. The court concluded that "the sentencing court was presented with a picture of Apelt's background that bore `no relation' to the picture presented by PCR counsel with apparently reliable evidence," and the "magnitude of the difference between the mitigating evidence that was presented at sentencing and the evidence that could have been presented through competent investigation is sufficient to undermine confidence in the outcome."

Arizona filed a motion for reconsideration, arguing that (1) the court committed manifest error by applying Martinez to excuse the procedural default of Claim 12, and (2) the court "erred in its assessment of Strickland's prejudice prong by failing to reweigh the totality of the mitigating evidence against the aggravating factors." The district court rejected the second argument, holding that it had taken "into account the aggravating factors as well as the totality of the mitigating evidence." The court explained its rejection of the first argument as follows:

In a footnote, the district court further noted that in Martinez, "the Arizona Attorney General's Office argued on remand that the presence of an alternative merits ruling meant that alternative ruling had to be reviewed under a deferential standard."

3. Claims 1-B & 1-D (Mental Competence at Trial and Sentencing)

Apelt asserted that he was "severely mentally ill and grossly overmedicated" when he was tried and that Villarreal was ineffective in failing to challenge his competence. The district court rejected this contention, noting that "co-counsel traveled to Germany, in part to investigate Apelt's placement in a psychological institution" and did not find any evidence to support a motion to determine competency. Moreover, "the record does not support a finding that Apelt lacked a rational and factual understanding of the proceedings or the ability to consult with counsel." Apelt was actively involved in his defense and the trial proceedings. In addition, his trial testimony revealed no traces of incompetence.

Furthermore, the district court determined that the fact that Apelt was on medication did not mean that he was unable to consult with his lawyer and understand the proceedings. See United States v. Shan Wei Yu, 484 F.3d 979, 985 (8th Cir. 2007). Also, the facts that he had been placed on suicide watch and had a history of mental health problems did not show that he was incompetent to stand trial. The court stated: "Apelt has failed to identify an instance in which he behaved irrationally, appeared not to understand the proceedings, or did not communicate effectively with Villarreal." The district court concluded that Apelt had not met his burden of showing IAC in Villarreal's failure to doubt his competency.

4. Claim 11 (Denial of Funds to Travel to Germany)

The district court reviewed the proceedings in the state courts and concluded that the denial of Villarreal's request for funds to travel to Germany was not unreasonable. Despite being given an opportunity to supplement his request, Villarreal never offered any specific information to support his request. Thus, he did not make a "threshold showing" that the additional funds would be helpful. Williams v. Stewart, 441 F.3d 1030, 1054 (9th Cir. 2006) (per curiam). The court held that "[b]ecause Villareal offered only `undeveloped assertions' in support of his request for funds to travel to Germany," the Arizona Supreme Court did not unreasonably apply Caldwell v. Mississippi, 472 U.S. 320, 323 n.1, 105 S.Ct. 2633, 86 L.Ed.2d 231 (1985), in denying this claim.

5. Claim 17 (failure to consider certain mitigating evidence)

Apelt argued that the Arizona Supreme Court erred by excluding from its consideration certain mitigating evidence in violation of Tennard v. Dretke, 542 U.S. 274, 124 S.Ct. 2562, 159 L.Ed.2d 384 (2004). The district court rejected this claim, finding that both the Arizona trial court and the Arizona Supreme Court considered all of Apelt's proffered mitigating factors.12

6. Claim 26 (intellectually disabled under Atkins)

The district court first noted that under Arizona law Apelt bore the burden of proving intellectual disability by clear and convincing evidence (A.R.S. § 13-753(G)), and that under AEDPA, Apelt had to show that the state court's decision was an unreasonable application of Atkins or was based on an unreasonable determination of the facts. Apelt focused on the state court's analysis of the evidence presented in the Atkins proceedings, objecting to the determinations that he had failed to show he had a subaverage intellect and had not shown significant deficits in adaptive behavior.

Although Apelt's experts, Dr. Kury and Dr. Ruff, concluded that Apelt suffered from "Mild Mental Retardation," and was intellectually disabled, the district court noted that Apelt had been tested as a child and found to have an overall IQ of 88. While the experts were skeptical about this test result, the district court noted that "the only specific challenge they offered was that Apelt would not have been placed in a special education school if his IQ had been that high." The court found this "unpersuasive as a criticism of the test because no one contests that Apelt's IQ was measured at 88 and, notwithstanding that result, he was in fact placed in a special education school."

Perhaps more important to the district court was the evidence of malingering: that Apelt sought to appear on the tests to be less intelligent than he is. Kury and Ruff administered eight separate IQ tests of Apelt and averaged them to arrive at a full-scale IQ score of 65, but the district court shared the state court's concern that these scores were the result of Apelt's malingering. The district court noted that Kury had detected "slight malingering" and that Ruff acknowledged it was possible Apelt malingered on some tests. Although Kury and Ruff doubted that the indications of malingering were strong enough to change their overall evaluations, they could not exclude the possibility that Apelt malingered or that all the testing data was reliable. The district court concluded that the state court had not clearly erred "by taking into account evidence of malingering in considering whether Apelt met his burden of establishing subaverage intelligence."

Although Apelt's experts opined that he suffered from significant deficits in adaptive behavior, particularly social/interpersonal skills, financial responsibility, functional academics, and work, Dr. Moran, Arizona's expert, thought "Apelt's conduct was actually indicative of anti-social personality disorder." The district court found that the state court was entitled to assess the relative credibility of the experts and that its decision to credit one qualified expert over the others was not enough to merit relief. The district court concluded that the state court did not clearly err when it found Apelt had failed to prove he met the adaptive behavior prong of intellectual disability and that the state court's ruling on the Atkins issue was not based on an unreasonable determination of facts.

7. Claim 27 (standard for proving in-tellectual disability)

Finally, the district court rejected Apelt's argument that Arizona had violated his right to due process and freedom from cruel and unusual punishment set forth in Cooper v. Oklahoma, 517 U.S. 348, 116 S.Ct. 1373, 134 L.Ed.2d 498 (1996), by requiring that he prove his intellectual disability. It noted that the Supreme Court in Atkins expressly permitted states to establish their own procedures for determining intellectual disability, and, thus, "there is no clearly established federal law setting a burden of proof in Atkins cases or extending Cooper to claims of intellectual disability."

The September 1, 2015 order concluded with the issuance of a certificate of appealability on two issues: denial of funds to travel to Germany, and the Atkins claim. The court also asked the parties to file supplemental briefs on whether an evidentiary hearing was necessary on IAC at sentencing.

H. The District Court's December 1, 2015 Order

No party thought that an evidentiary hearing was necessary, but Arizona filed a motion for reconsideration, which the district court denied. In doing so, the court expanded on its reasons for granting relief. The court noted that Villarreal's initial presentation of mitigation omitted evidence directly contradicting the assertion that Apelt's childhood was normal. However, PCR counsel presented evidence "of extreme poverty, physical abuse, developmental delays, and mental health problems," and these allegations of prejudice were strengthened by the record developed in the Claim 12 proceedings. The district court noted that: (1) Apelt's father was cruel to his children and beat them; (2) the father sexually abused his children; (3) Apelt suffered extreme stress as a result of his father's abuse; (4) Apelt's childhood development was delayed and he had difficulty maintaining his hygiene and dressing appropriately; (5) Apelt attended a special school for learning disabled and mentally retarded children and left school when he reached ninth grade; (6) he had difficultly maintaining employment, even in unskilled labor; (7) Apelt was discharged from compulsory military service for "mental inadequacy"; and (8) Apelt was sent to a psychiatric institution after a suicide attempt. The district court reasoned:

The district court also rejected Arizona's assertion that the three aggravating factors outweighed the totality of the mitigating evidence. It cited Correll v. Ryan, 539 F.3d 938, 951-52 (9th Cir. 2008), as holding that to establish prejudice under Strickland it is not necessary to show that the newly discovered mitigation evidence "would necessarily overcome the aggravating circumstances." It noted that, although three aggravating factors were found, "under Arizona law the pecuniary gain and procuring factors are not both entitled to `full weight.'" In addition, the court observed that the Ninth Circuit in Stankewitz v. Woodford, 365 F.3d 706, 717-18 (9th Cir. 2004), recognized that the Supreme Court had made clear that the failure to present mitigating evidence could be prejudicial even when the defendant's actions were egregious. The order concluded with the reiteration that "Villareal's representation at sentencing was inadequate and prejudiced Apelt," and that, had he "performed a competent mitigation investigation, there is a reasonable probability that Apelt would not have been sentenced to death."

II.

The district court's grant or denial of habeas relief is reviewed de novo. Moses v. Payne, 555 F.3d 742, 750 (9th Cir. 2009).

A. The state court's finding of procedural default must be considered, but does not preclude federal judicial review.

As a threshold issue, Arizona asserts that the district court was barred from reaching the merits of Apelt's IAC claims because these claims were procedurally barred under Arizona law, and Apelt cannot excuse his default under Martinez, 566 U.S. 1, 132 S.Ct. 1309. It appears that the district court may have misinterpreted our decision in Clabourne, 745 F.3d 362, overruled on other grounds by McKinney v. Ryan, 813 F.3d 798, 818 (9th Cir. 2015) (en banc). Nonetheless, reviewing the district court's comprehensive consideration of Apelt's petition, we conclude that the district court implicitly determined that Apelt met the cause and prejudice standard set forth in Coleman v. Thompson, 501 U.S. 722, 111 S.Ct. 2546, 115 L.Ed.2d 640 (1991), and thus could address the merits of Apelt's IAC claims.

1. We review the state court's procedural default ruling on its merits.

The district court's treatment of Martinez is not a model of clarity. Leading up to its consideration of Apelt's claims on their merits, the district court wrote:

The district court then addressed Apelt's claims under the standard set forth in AEDPA, 28 U.S.C. § 2254(d). However, it did not explicitly address Arizona's assertion that Apelt's IAC claim was procedurally barred.13

Nonetheless, the clear import of the district court's language is that it was abiding by our direction in Clabourne to review the state court's merits decision under AEDPA's deferential standard. Following Martinez, if a state court had determined that a constitutional issue was procedurally defaulted, and the federal habeas court subsequently determined that the procedural default was excused, then the federal court would apply a de novo standard of review as there was no state court determination on the merits to which the federal court could defer. Our opinion in Clabourne clarified that when a state court "double-barrels" its decision — holding that a claim was procedurally barred and denying the claim on its merits — both its procedural default ruling and its merits ruling are entitled to deferential review by federal courts, as intended by AEDPA.

Accordingly, the district court's orders should not be construed as holding that, because the state court reached the merits of Apelt's claim, the federal court can ignore the procedural default. In Zapata v. Vasquez, 788 F.3d 1106, 1111 (9th Cir. 2015), we reiterated that, where a state court expressly invokes a procedural bar, the claim is defaulted, even though the state court goes on to discuss the merits of the claim. See also Harris v. Reed, 489 U.S. 255, 264 n.10, 109 S.Ct. 1038, 103 L.Ed.2d 308 (1989).

Here, the state trial court clearly held that the IAC claims were precluded under Arizona law before determining that Apelt had failed to show that counsel's performance fell below objective standards of reasonableness and failed to show that there was a reasonable probability that the result of sentencing would have been different. Accordingly, we first consider whether Apelt's IAC claim is procedurally barred.

Martinez is properly understood as building on Coleman. Coleman set forth the requirement that, in order to obtain federal habeas relief, a state prisoner must establish cause to excuse a procedural default in state court, as well as prejudice. 501 U.S. at 730-31, 111 S.Ct. 2546. Martinez embraced the causation requirement, but held that a prisoner could establish causation by showing two things: (1) where he had counsel in the initial collateral review proceeding, that the attorney was ineffective under the standards of Strickland; and (2) "that the underlying ineffective-assistance-of-trial-counsel claim is a substantial one, which is to say that the prisoner must demonstrate that the claim has some merit." Martinez, 566 U.S. at 14, 132 S.Ct. 1309. Indeed, the Supreme Court explained that, "[w]hen faced with the question whether there is cause for an apparent default, a State may answer that the ineffective-assistance-of-trial-counsel claim is insubstantial, ... or that the attorney in the initial-review collateral proceeding did not perform below constitutional standards." Id. at 15-16, 132 S.Ct. 1309.14

Under Coleman and Martinez, the district court's determinations — both that it could reach the merits of Apelt's IAC claims and its evaluation of the merits of Apelt's IAC claims — turn on three inquiries: (1) whether Villarreal, as Apelt's counsel on his first PCR, was ineffective under Strickland; (2) whether Villarreal's performance as counsel at sentencing was ineffective under Strickland; and (3) whether Apelt was prejudiced by Villarreal's performances.

2. Arizona's contentions that Martinez and Coleman are inapplicable are not persuasive.

Arizona advances two arguments for holding that the district court could not reach the merits of Apelt's IAC claims. Arizona first argues that the purpose behind the exception recognized in Coleman and Martinez is a concern that no court will consider a state defendant's constitutional claim of trial counsel IAC. It thus reasons that, because the trial court reached the merits of Apelt's IAC claims, there is no need for the exception because one court did consider Apelt's contentions on their merits.

Although Arizona cites selected language from Martinez, we do not find its argument persuasive. Its proposed "one and done" approach, rather than narrowing federal habeas review, would bar federal review of constitutional issues. It contends that the fact that one state court had addressed the constitutional issues on the merits, blocks federal habeas review, regardless of the reasonableness of the state court's decision. However, even if the fact that one state court had considered the constitutional claim were sufficient to distinguish Martinez, a petitioner, such as Apelt, would still be eligible to meet the cause and prejudice standard set forth in Coleman. There, the Court stated:

501 U.S. at 750, 111 S.Ct. 2546. Thus, even if Apelt's proceedings do not come within the coverage of Martinez, the procedural default might still be excused under Coleman.

Second, Arizona asserts that because the state court denied Apelt's PCR on the merits, Apelt cannot show that the failure to raise IAC claims in the first post-conviction petition was prejudicial. In other words, because the state court rejected the IAC claims on their merits in the PCR, it follows that there was no prejudice from the failure to raise the claims in the first post-conviction petition, and, thus, Apelt is not entitled to federal habeas review under Martinez.

Again, Arizona's argument seeks to place Apelt's constitutional claim beyond even deferential review by a federal court. Certainly, the state court's decision on the PCR is relevant to a determination of whether the failure to raise IAC claims in the first post-conviction petition was prejudicial. But that determination is not in itself a complete bar to federal habeas review — particularly where, as here, the state court's merits ruling on the PCR is a conclusory alternate ruling.

In sum, while the state court's alternate ruling on the merits of the IAC claims does not allow a federal court to ignore the procedural default ruling, it also does not bar a federal court from applying Martinez and Coleman.

3. Villarreal was ineffective as counsel on the postconviction petition.

In support of his assertion that Villarreal was ineffective as post-conviction counsel, Apelt asserts: (1) Villarreal was conflicted from raising his own ineffectiveness at sentencing; (2) Villarreal squandered Apelt's opportunity for a thorough, well-investigated post-conviction petition when he prematurely filed a post-conviction petition; (3) Villarreal failed to comply with well-established professional norms that in 1989 required that counsel, in a capital case, be familiar with all state and federal post-judgment options, discuss them with his client, and conduct thorough investigations into all meritorious issues, particularly claims of IAC; and (4) the failure to investigate was not, and could not have been, the product of strategy.15

Arizona responds that Apelt's conflict-of-interest argument is foreclosed by Ortiz v. Stewart, 149 F.3d 923 (9th Cir. 1998), and Bonin v. Calderon, 77 F.3d 1155 (9th Cir. 1996). However, these cases were decided before Martinez and were premised on the lack of a constitutional right to counsel in a habeas proceeding.16 At that time, a post-conviction lawyer's negligence did not qualify as cause because the lawyer was considered the prisoner's agent. See Lopez v. Ryan, 678 F.3d 1131, 1133 (9th Cir. 2012) (noting that Coleman "held that a PCR lawyer's negligence does not qualify as cause, because the lawyer is the prisoner's agent"). Martinez, however, recognized that "inadequate assistance of counsel at initial-review collateral proceedings may establish cause for a prisoner's procedural default of a claim of ineffective assistance of counsel." Lopez, 678 F.3d at 1133 (quoting Martinez, 566 U.S. at 9, 132 S.Ct. 1309). Accordingly, Martinez overruled the premise of the rulings in Stewart and Bonin, giving life to conflict-of-interest assertions.

We glean guidance from our opinion in United States v. Del Muro, 87 F.3d 1078 (9th Cir. 1996). There, we commented:

87 F.3d at 1080.

A similar situation may exist where a defendant is represented on appeal by his trial attorney. The attorney may be torn between his duty to represent his client and a desire to defend the reasonableness of his performance at trial. Here, it is possible that Villarreal's prompt filing of a postconviction petition, based on the specialist's testimony in Rudi's trial, was partially fueled by a desire to avoid litigating his performance at sentencing.

Arizona also argues that the court should defer to Villarreal's decision to file a post-conviction petition while the direct appeal was pending and, that, even if doing so was "unusual," this does not necessarily make it ineffective. Although other counsel could have chosen other routes, Arizona maintains that Villarreal's choice fell well within the wide range of professional competence.

On the record in this case, it is very difficult to justify Villarreal's decision. His client had been found guilty of a horrendous murder and given the death penalty. Rather than take the time to investigate the case, as required by the applicable professional norms, he forfeited all other arguments that could be raised in a postconviction petition, including IAC, to argue that Dr. DiMaio's testimony, in Rudi's trial, that Cindy's murderer was right handed, exonerated Apelt, who is left handed. This was not objectively reasonable. There was overwhelming evidence that Apelt and Rudi committed the crime together, regardless of which one actually killed Cindy. Moreover, even if the argument had some potential for reducing Apelt's sentence, there was no need or reason to rush filing the post-conviction petition before all the other possible issues had been researched. In sum, the record supports a determination that Apelt's challenge to Villarreal's performance as postconviction counsel is "substantial." Martinez, 566 U.S. at 14, 132 S.Ct. 1309; see also Miller-El v. Cockrell, 537 U.S. 322, 336, 123 S.Ct. 1029, 154 L.Ed.2d 931 (2003) (holding that for a certificate of appealability to issue, a petitioner must show that reasonable jurists could debate whether the issue should have been resolved in a different manner or that the claim was "adequate to deserve encouragement") (citation omitted).

B. Villarreal was ineffective at sentencing.

Having determined that Villareal's performance on Apelt's first post-conviction petition was sufficiently deficient as to provide cause for Apelt's default, see Coleman, 501 U.S. at 750, 111 S.Ct. 2546, we consider whether Villarreal's performance as counsel at sentencing was ineffective under Strickland v. Washington, 466 U.S. 668, 104 S.Ct. 2052, 80 L.Ed.2d 674 (1984).

Arizona objects to the district court's determination of IAC asserting that the state courts' rejection of these claims were neither contrary to, nor an unreasonable application of, clearly established federal law. In particular, Arizona argues that: (a) the alleged failure to adduce mitigating evidence is the same ilk as the errors in Strickland, Darden v. Wainwright, 477 U.S. 168, 106 S.Ct. 2464, 91 L.Ed.2d 144 (1986), and Burger v. Kemp, 483 U.S. 776, 107 S.Ct. 3114, 97 L.Ed.2d 638 (1987); (b) clearly established federal law refers only to Supreme Court holdings; and (c) the district court did not explain why the state court's decision was contrary to Strickland.

Some of Arizona's arguments, however, are slightly off point because the essence of the district court's determination was factual. Habeas relief was granted not for a failure to follow clearly established federal law, 28 U.S.C. § 2254(d)(1), but because, applying clearly established federal law, the determination that Villarreal was not ineffective under the standard of Strickland was "an unreasonable determination of the facts in light of the evidence presented in the State court proceeding." 28 U.S.C. § 2254(d)(2).

Nonetheless, Darden and Burger inform our decision in this matter. In Darden, IAC was only one of Darden's claims. He argued that his trial attorneys "did not delve sufficiently into his background, and as a result were unprepared to present mitigating evidence at the sentencing hearing." 477 U.S. at 184, 106 S.Ct. 2464. In rejecting Darden's claim, the Supreme Court noted that defense counsel had "engaged in extensive preparation prior to trial, in a manner that included preparation for sentencing." Id. Counsel expended hundreds of hours on Darden's behalf, including "investigating petitioner's alibi, and driving petitioner around the scene of events to establish each point of his story," and "obtain[ing] a psychiatric report on petitioner, with an eye toward using it in mitigation during sentencing." Id. at 185, 106 S.Ct. 2464.

The Court further noted that there were several reasons why counsel could have reasonably chosen to rely on a simple plea for mercy. Id. at 186, 106 S.Ct. 2464. "Any attempt to portray petitioner as a nonviolent man would have opened the door for the State to rebut with evidence of petitioner's prior convictions." Id. "In addition, if defense counsel had attempted to offer testimony that petitioner was incapable of committing the crimes at issue here, the State could have responded with a psychiatric report that indicated that petitioner `very well could have committed the crime.'" Id. "[I]f defense counsel had attempted to put on evidence that petitioner was a family man, they would have been faced with his admission at trial that, although still married, he was spending the weekend furlough with a girlfriend." Id. Accordingly, the Court concluded that counsel's decision, after consulting with Darden, not to use the psychiatric testimony was reasonable.

In Burger, IAC was a secondary issue.17 Burger's attorney had "offered no mitigating evidence at all." 483 U.S. at 788, 107 S.Ct. 3114. However, the Supreme Court reviewed the counsel's extensive investigation that led to the decision not to present mitigating evidence. Id. at 789-91, 107 S.Ct. 3114. The Court also noted that counsel had considered calling Burger's mother and a lawyer who had acted as Burger's big brother, but concluded that "it was surely not unreasonable for [counsel] to have concluded that cross-examination might well have revealed matters of historical fact that would have harmed his client's chances for a life sentence." Id. at 792, 107 S.Ct. 3114. It further commented that "petitioner's present counsel — even with the benefit of hindsight — has submitted no affidavit from that lawyer establishing that he would have offered substantial mitigating evidence if he had testified." Id. at 793, 107 S.Ct. 3114. In sum, the Court, although troubled by counsel's actions, concluded that Burger had not shown that his actions "were outside the wide range of professionally competent assistance." Id. at 795, 107 S.Ct. 3114 (citation omitted).

Counsels' efforts in Darden and Burger stand in contrast to Villarreal's minimal efforts to investigate Apelt's background. It is particularly noteworthy that defense counsel in those cases procured psychiatric reports on the defendants even though they ultimately decided not to present the reports at sentencing.

Arizona also argues that the state court properly rejected Villarreal's request for funds to travel to Germany and that Villarreal adequately investigated mitigation evidence. Arizona notes that Villarreal's co-counsel traveled to Germany in hope of obtaining evidence of Apelt's difficult childhood, and that Villarreal contacted the German consulate and Amnesty International.

These arguments are not persuasive as they ignore the troubling information that Villarreal had and misstate some of the facts. The very fact that Villarreal's co-counsel traveled to Germany and sought information as to Apelt's "difficult childhood" suggests that Villarreal recognized the potential importance of such information. Moreover, co-counsel's failure to procure the background information was not because it didn't exist, but because Apelt's family members didn't speak English. Also, counsel knew, or should have known, that Apelt, while in jail, was prescribed a number of medications, was placed on suicide watch for five days, and was admitted to the Psychiatric Unit on at least one occasion. This information appears to be the type that would prompt counsel to obtain a psychiatric report on the defendant, as counsel did in Darden and Burger. Furthermore, the record refutes Arizona's suggestions that Villarreal utilized Amnesty International and that the German consulate was of assistance.

Moreover, Villarreal stated that his failure to investigate mitigation evidence was not a strategic choice, and that Apelt did not take an active part in the development of mitigating evidence. Indeed, it is difficult to imagine any rational basis for not investigating Apelt's mental health and childhood. Apelt was facing the death penalty for committing a horrendous, cold-blooded murder. The documents that counsel had received the night before sentencing that allegedly attested to Apelt's good character were unlikely to have any impact on the judge.18 Furthermore, these documents were more than offset by the testimony of Detective Davis, who spoke German, had traveled to Germany, and testified to Apelt's criminal activity and poor character in Germany. The record shows that Villarreal was unprepared to respond to Detective Davis's testimony.

We do not have the benefit of the state courts' reasons for rejecting Apelt's IAC claim on his PCR. The state trial court offered only the conclusive statement that Apelt had failed "to make a sufficient preliminary showing that counsel's performance fell below objective standards of reasonableness." The Arizona Supreme Court summarily denied Apelt's petition for review.

Nonetheless, as required by Richter, 562 U.S. at 102, 131 S.Ct. 770, we consider "what arguments or theories supported or, as here, could have supported, the state court's decision," and "ask whether it is possible fairminded jurists could disagree that those arguments or theories are inconsistent with the holding in a prior decision of this Court."

Here, we determine that this record compels a finding that Villarreal's performance at the capital hearing sentence "fell below an objective standard of reasonableness," even in 1989. Id. at 104, 131 S.Ct. 770 (quoting Strickland, 466 U.S. at 688, 104 S.Ct. 2052). There can be no doubt that counsel was required to review a defendant's background in preparation for sentencing. Indeed, the record shows that Villarreal knew this but failed to take the steps necessary to do so. After all, Apelt had spent his whole life in Germany until he came to the United States some six months before committing the murder. The trial court's reluctance to fund Villarreal's requested travel to Germany simply does not excuse Villarreal's failure to make the supplemental showing requested by the trial court, nor does it excuse his failure to consider other means of investigating Apelt's mental health and background. He did not seek a psychiatric evaluation of Apelt despite the nature of the crime, Apelt's treatment while incarcerated before trial, and other indicia of possible psychiatric issues. Accordingly, we agree with the district court that "[n]o fairminded jurist could conclude Villareal's performance was sufficient."

C. The state courts' determination that counsel's inadequate representation of Apelt at sentencing was not prejudicial is not unreasonable.

While we agree with the district court that Villarreal's performance at sentencing was inadequate, we cannot find, as required by the Supreme Court, that the state courts' finding of no prejudice was "objectively unreasonable." Woodford v. Visciotti, 537 U.S. 19, 27, 123 S.Ct. 357, 154 L.Ed.2d 279 (2002).

The Supreme Court stated in Richter:

562 U.S. at 104, 131 S.Ct. 770 (parallel cites omitted). The Court explained:

562 U.S. at 111-12, 131 S.Ct. 770 (parallel cites omitted).

Critically, in a federal habeas petition where the petitioner is challenging counsel's performance, the question "`is not whether a federal court believes the state court's determination' under the Strickland standard `was incorrect but whether that determination was unreasonable — a substantially higher threshold.'" Knowles v. Mirzayance, 556 U.S. 111, 123, 129 S.Ct. 1411, 173 L.Ed.2d 251 (2009) (quoting Schriro v. Landrigan, 550 U.S. 465, 473, 127 S.Ct. 1933, 167 L.Ed.2d 836 (2007)). Thus, our review of the state court decision is "doubly deferential." Pinholster, 563 U.S. at 190, 131 S.Ct. 1388 (quoting Knowles, 556 U.S. at 123, 129 S.Ct. 1411). Accordingly, "[w]hen § 2254(d) applies, the question is not whether counsel's actions were reasonable. The question is whether there is any reasonable argument that counsel satisfied Strickland's deferential standard." Richter, 562 U.S. at 105, 131 S.Ct. 770.

In addition, the Supreme Court directs that even "[w]here a state court's decision is unaccompanied by an explanation, the habeas petitioner's burden still must be met by showing there was no reasonable basis for the state court to deny relief." Id. at 98, 131 S.Ct. 770.

In Andrews v. Davis, 866 F.3d 994 (9th Cir. 2017), we read Supreme Court precedent as establishing three steps for applying Strickland to determine whether counsel's deficient performance prejudiced the defendant at the penalty phase of a state capital case. Id. at 1020. First, the court evaluates and weighs the totality of the available mitigating evidence; second, it evaluates and weighs "the aggravating evidence and any rebuttal evidence that could have been adduced by the government had the mitigating evidence been introduced"; and third, it reweighs "the evidence in aggravation against the totality of available mitigating evidence ... to determine `whether there is a reasonable probability that, absent the errors, the sentencer ... would have concluded that the balance of aggravating and mitigating circumstances did not warrant death.'" Id. (quoting Strickland, 466 U.S. at 695, 104 S.Ct. 2052). In Andrews, we reversed the district court's grant of a writ because we found that the California Supreme Court's determination that the denial of effective counsel was not prejudicial was not an unreasonable application of Strickland. Id. at 1033. We reach a similar conclusion in this case.

Apelt clears the first hurdle as the proffered mitigating evidence paints a very different picture of Apelt's background and character than was presented at sentencing. Apelt probably clears the second hurdle, mostly because there is little evidence in the record as to what rebuttal evidence Arizona might have produced in response to the mitigating evidence proffered in the PCR.19 However, Apelt fails to clear the third hurdle: he has not shown that, after reweighing the aggravating and mitigating evidence, there is a reasonable probability that, absent the errors, the sentencer would have concluded that the balance of aggravating and mitigating circumstances did not warrant death. Therefore he has not shown that the state courts' determination of no prejudice is so unreasonable that no reasonable jurist could agree with it.

Apelt cites cases such as Williams, 529 U.S. 362, 120 S.Ct. 1495, Wiggins v. Smith, 539 U.S. 510, 123 S.Ct. 2527, 156 L.Ed.2d 471 (2003), and Stankewitz, 365 F.3d 706, as showing that neither the brutality of the underlying murder, nor the defendant's prior criminal acts, excuse counsel's failure to investigate the defendant's background. Apelt's argument is fair, but overlooks a critical distinction. In all three of those cases, the murders were not planned: rather than being premeditated, the murders were the result of other motives, such as robbery and kidnaping.

Here, Cindy's murder was premeditated and calculated. The record shows that from the time Apelt entered the United States around Labor Day 1988, he lied to and manipulated others, and borrowed and stole money from women. He was intent on marrying a woman for her money. In less then a month he proposed to three different women. He convinced Cindy to secretly marry him in Las Vegas by leading her to believe that he was wealthy. A little over a week after the marriage, Apelt visited an insurance broker seeking to take out a million dollar insurance policy on Cindy's life. As borne out by subsequent events, Apelt's unwavering intent was to murder the woman he had convinced to marry him in order to collect on the insurance policy.

When the insurance broker indicated that they could not obtain a million dollar policy, Apelt and Cindy filled out an application for a $400,000 policy. When the company did not accept the application for a $400,000 policy, Apelt agreed to take out two policies, one for $100,000 and another for $300,000. All of these applications were paid for by Cindy.

In early December, Apelt told Anke that Cindy had a lot of insurance and that if she died an unnatural death, he would be rich. At about the same time, Anke and Rudi reserved a rental car with a good-sized trunk, but cancelled the reservation a couple of days later. On December 22, the insurance agent told Apelt and Cindy that the two insurance policies were in effect.20 The next day Rudi and Anke returned to the car rental agency and rented the car with a large trunk. Apelt told Rudi and Anke that they would have lots of money if they would "go out and kill Cindy." That night Apelt drove Cindy out into the desert and he and Rudi murdered her.

Apelt acted as if he had no involvement in Cindy's murder. He pretended to wait for her for a late dinner at a restaurant, penned a fake note to Cindy to that effect, and cried in the presence of a police officer when Cindy's sister reported that Cindy was missing. After Cindy's body was discovered, Apelt continued to deny any knowledge of her death. He went to the insurance agent seeking assistance to obtain money so that he could attend Cindy's funeral in Illinois, and eventually obtained a $2,000 loan, using the life insurance policy as collateral. Apelt flew to Illinois, attended the funeral, and broke down in tears when he tried to speak at the funeral.

Meanwhile, Apelt continued to scheme in order to get away with murder. When, on December 28, he returned the rental car in which he had driven Cindy into the desert, the two front tires had multiple flat spots caused by aggressive harsh driving, thereby making it difficult to trace any tire pattern. On January 3, Apelt flew to Los Angeles and paid a homeless person to leave a message on Cindy's answering machine. At trial, Apelt maintained his innocence and from jail attempted to get a note to Rudi instructing him on an alibi.

Although he had opportunities to abandon his scheme, Apelt relentlessly pursued his scheme to murder the woman he professed to love and had married, and he involved his brother, Rudi, and Anke in the murder and the cover-up. Nothing in the record indicates that any explanation for why Apelt became a monster would have changed the sentence.

This conclusion is all the more reasonable as none of the proffered mitigating evidence excuses Apelt's callousness, nor does it reduce Apelt's responsibility for planning and carrying out the murder. Indeed, presenting Apelt's upbringing and activities in Germany to explain how Apelt became a calculating killer arguably could weigh in favor rather than against the death penalty. See Pinholster, 563 U.S. at 201, 131 S.Ct. 1388 (noting that the "new evidence relating to Pinholster's family — their more serious substance abuse, mental illness, and criminal problems ... — is also by no means clearly mitigating, as the jury might have concluded that Pinholster was simply beyond rehabilitation").

In sum, even assuming that we might have looked more favorably on Apelt's PCR than the state trial court, we cannot conclude that there is no reasonable argument that Apelt was not prejudiced. The evidence of Apelt's depravity is overwhelming. At the age of 25, Apelt concocted and carried out a calculated plan to marry Cindy, to have her pay for her own life insurance, and then, as soon as the insurance premium was paid, to viciously and cruelly murder her. Furthermore, he persuaded his younger, intellectually-challenged brother to participate in the scheme and the actual murder. We cannot say that it would be unreasonable to conclude that further evidence as to how Apelt became such a monster would have had no effect on his sentence. Accordingly, we vacate the district court's grant of the writ.

D. Apelt has not shown that the state court's denial of funding to investigate mitigation violated his constitutional rights.

Apelt asserts that the trial court "eliminated any opportunity for an individualized sentencing and a presentation of mitigation" when it denied counsel funds for travel to Germany. He argues that this violated his rights under the Eighth and Fourteenth Amendments to individualized sentencing. See Ake v. Oklahoma, 470 U.S. 68, 77, 105 S.Ct. 1087, 84 L.Ed.2d 53 (1985) (noting that "a criminal trial is fundamentally unfair if the State proceeds against an indigent defendant without making certain that he has access to the raw materials integral to the building of an effective defense"). Apelt claims that the Arizona Supreme Court's determination that he had not made an adequate showing of need "was both an unreasonable application of and contrary to clearly established federal law."

We agree with the district court that, because Villarreal had offered only "undeveloped assertions" in support of his request for funds, the Arizona Supreme Court's denial of relief was not unreasonable. In Caldwell v. Mississippi, 472 U.S. 320, 105 S.Ct. 2633, 86 L.Ed.2d 231 (1985), the Supreme Court commented that, because the petitioner in that case offered little more than "undeveloped assertions that the requested assistance would be beneficial," the denial of requests for a ballistics expert was not a denial of due process. Id. at 323 n.1, 105 S.Ct. 2633. In Williams v. Stewart, 441 F.3d 1030 (9th Cir. 2006), we stated that the then "present rule is that an indigent defendant has a constitutional right to investigative services, but that such right comes into existence only when some need is demonstrated by the defendant." Id. at 1053-54 (quoting Smith v. Enomoto, 615 F.2d 1251, 1252 (9th Cir. 1980)).

In light of this federal law, the Arizona Supreme Court's denial of relief was not unreasonable. The court cited Caldwell and found that Apelt's assertion of "prior psychiatric hospitalization, his difficult childhood, and his low education level," were insufficient to compel funding.21 Apelt, 861 P.2d at 651-52. Perhaps, as Apelt asserts, today reasonable jurists would be compelled to conclude that the investigation of a capital defendant's background and mental history is so fundamental to the presentation of an adequate defense that there is no need to demonstrate or explain why it might be relevant.22 However, based on the existing federal law in 1989, the Arizona Supreme Court's decision — which was based on a record that by and large refuted the need for the proposed investigation — was not so outlandish that no reasonable jurists could agree with it. The district court's denial of relief on Apelt's challenge to the state courts's denial of funding to investigate mitigating evidence is affirmed.

E. Apelt has not shown that he is entitled to relief under Atkins.

1. Apelt's Contentions

Apelt bases his argument on the Supreme Court's opinions in Atkins and Hall v. Florida, ___ U.S. ___, 134 S.Ct. 1986, 188 L.Ed.2d 1007 (2014), that "the Eighth Amendment bars the execution of people who are intellectually disabled according to current medical standards." He accepts that the applicable Arizona statute, A.R.S. § 13-753(K)(3), defines intellectual disability as requiring a showing of (a) significant subaverage general intellectual functioning, (b) concurrent significant impairment in adaptive behavior, and (c) onset before the defendant reached the age of 18.

Apelt argues that the evidence shows that he "suffers significantly subaverage intellectual functioning." Dr. Ruff conducted a neuropsychological examination of Apelt in 2000 and determined he had a full-scale IQ of 61, and Dr. Kury conducted his own examination in 2004 and found Apelt's full-scale IQ to be 65. Apelt argues the only "evidence" that he had a higher IQ was the reported result of a test given Apelt in Germany when he was nine years old, which is unreliable because there is no evidence as to how it was administered.

Apelt also challenges the state court's determination that he was "malingering" and that accordingly the results of the tests administered in 2000 and 2004 are not accurate. Apelt argues that neither Dr. Ruff nor Dr. Kury opined that he was malingering during the test. Rather, they testified that, even if Apelt had attempted to malinger, their conclusions remained sound.

Addressing the second prong of the intellectual disability test, Apelt argues that Drs. Ruff and Kury agreed that he suffers significant impairments in adaptive behavior, and that the state court disregarded this testimony in concluding that Apelt was "able to meet society's expectations of him." He argues the state court improperly relied on the Arizona Supreme Court's opinion in State v. Grell, 212 Ariz. 516, 135 P.3d 696 (2006), insofar as that case "permits the state court to disregard evidence of adaptive behavior deficits." Apelt argues that he demonstrated numerous deficits in adaptive behavior including the areas of "memory and orientation, managing money, home and transportation, health and safety, social adjustment, [and] functional academics." He asserts that all three experts agreed he suffers major deficits in his adaptive behavior.

In addition, Apelt challenges the state court's reliance on his past employment, military discharge, and marriage. He asserts that he was only able to obtain unskilled work and never held a job for very long, his military discharge was due to "mental inadequacy," and his marriage lasted for only two years during which time his wife abused him mentally and physically. Apelt notes that he never lived on his own. During his stay in the United States, he lived in a motel, where he was not required to prepare meals or perform housekeeping duties, or with Cindy upon whom he relied to help him obtain identification and the paperwork necessary to get a job at Olive Garden.

Apelt objects that the state court "improperly relied on the facts of the crime to support its conclusion that Mr. Apelt does not have the requisite adaptive behavior deficits to qualify for a diagnosis of intellectual disability." He argues that the American Association on Intellectual and Development Disabilities does not permit the use of criminal behavior to assess adaptive behavior deficits. Moreover, he criticizes the state court for emphasizing his strengths because it is well-recognized that intellectually disabled people can possess strengths along with weaknesses. He similarly asserts that the state court "erred by placing too much emphasis on Mr. Apelt's adaptive behavior as an adult and post-incarceration."

Finally, addressing the third prong of the test, Apelt notes that every expert "agreed the 88 score [on the test he took when he was a child] was erroneous and/or lacked the necessary foundation for professional consideration in the intellectual disability evaluation." Thus, left with two reliable IQ scores of 61 and 65, the only reasonable inference is that Apelt's limitation arose before he was 18, as reflected in his childhood behavior and assignment to a special school.

2. Apelt has not met his burden of showing that the state court's denial of his Atkins claim is an unreasonable determination of the facts in light of the evidence presented.

To prevail on his Atkins claim, Apelt must meet all three prongs of the test for intellectual disability.23 State v. Boyston, 231 Ariz. 539, 543, 298 P.3d 887, 891 (2013). His experts tested Apelt and determined that his IQ was 61 or 65. The only evidence that he had a higher IQ was the result of a test administered in Germany when he was nine on which he scored an 88. But there is no evidence as to the reliability of the German test, and even Arizona's expert, Dr. Moran, questioned the accuracy of this test. Furthermore, the placement of Apelt into an elementary school for intellectually disabled and learning disabled children is at least some evidence that the German school administrators recognized that Apelt was intellectually disabled, despite the 88 score. Accordingly, the totality of the evidence would support the conclusion that Apelt had a "subaverage general intellectual functioning" before he reached the age of 18.

However, Apelt's Atkins claim fails because the record fairly supports the state courts' determination that Apelt does not suffer from significant deficits in adaptive behavior. While Apelt focuses on his experts' findings that he suffered major deficits in his adaptive behavior, Arizona's expert, Dr. Moran, disagreed, and the state court could credit one expert over another. More importantly, Apelt does not really address the strongest evidence of his adaptive behavior: the record of his activities in the United States. The state court commented:

Indeed, Apelt's activities in the United States reflect ingenuity, cleverness, and an ability to manipulate others. Accordingly, we cannot find that the state court's determination was not supported by substantial evidence or is unreasonable. The district court's denial of relief on Apelt's Atkins claim is affirmed.

F. Uncertified Issues

As allowed by Ninth Circuit Local Rule 22-1(e), Apelt's brief raised two uncertified claims for relief: (1) the Arizona Supreme Court applied an unconstitutional causal connection requirement to his mitigation evidence; and (2) counsel was ineffective at trial and sentencing for failing to challenge Apelt's competency. Pursuant to Ninth Circuit Local Rule 22-1(f), we asked Arizona to respond to the uncertified issues. Arizona did, and we hereby certify the issues for appeal, and deny Apelt's claims on their merits. See Buck v. Davis, ___ U.S. ___, 137 S.Ct. 759, 773, 197 L.Ed.2d 1 (2017).

1. Apelt's claim that the Arizona Supreme Court applied an unconstitutional causal nexus requirement is not persuasive.

Apelt asserts that, when reviewing his conviction and sentence, the Arizona Supreme Court applied an unconstitutional causal nexus requirement by: (a) stating that he "has failed to advance any credible argument as to why some factors should be considered mitigating at all"; (b) discounting the history of psychiatric hospitalization because he "did not explain why hospitalization might be mitigating"; and (c) rejecting his challenge to the lack of mitigation funding because he "did not offer any reason why a difficult childhood and lack of education would be mitigating." Apelt, 861 P.2d at 651, 653-54. Apelt argues that since Lockett v. Ohio, 438 U.S. 586, 98 S.Ct. 2954, 57 L.Ed.2d 973 (1978), the Supreme Court has defined mitigation as anything about a defendant's character or record that the defendant proffers as a basis for a sentence less than death, and that in McKinney v. Ryan, 813 F.3d 798, 819 (9th Cir. 2015) (en banc), we held that the Arizona Supreme Court had acted contrary to Lockett and Eddings v. Oklahoma, 455 U.S. 104, 102 S.Ct. 869, 71 L.Ed.2d 1 (1982), in imposing a causal nexus requirement when it independently reviewed death sentences.

Specifically, Apelt argues that, although the Arizona Supreme Court did not cite State v. Ross, 180 Ariz. 598, 886 P.2d 1354 (1994) — which the Ninth Circuit disapproved of in McKinney — it did cite State v. Wallace, 160 Ariz. 424,773 P.2d 983, 986 (1989), when it rejected his denial of resources claim.24 Ross was not decided until after the Arizona Supreme Court issued its opinion in Apelt, but Wallace, which also used an unconstitutional causal nexus requirement, was decided four years prior to Apelt. Apelt contends that the reference to Wallace coupled with the Arizona Supreme Court's conclusion that it found "no mitigating factors" demonstrates that the court followed the practice condemned in McKinney of disregarding certain mitigating factors. Finally, Apelt argues that even if the Arizona Supreme Court's rejection of his mitigation is not based on a lack of causal nexus, it remains unconstitutional under Eddings and Lockett because the United States Supreme Court has held that a defendant's good behavior is mitigating.

The district court, which addressed the causal nexus claim before we issued our en banc opinion in McKinney, denied Apelt relief. The district court found Apelt's claim to be unsupported by the record. The district court noted that the trial court had expressly stated that it had considered all of Apelt's proffered mitigation, and suggested that the trial court's statement was "virtually dispositive of Apelt's claim." See Parker v. Dugger, 498 U.S. 308, 314-15, 111 S.Ct. 731, 112 L.Ed.2d 812 (1991). The district court continued:

In McKinney, we explained:

813 F.3d at 821. In addition, we held that an Eddings error was not structural error, and, therefore, McKinney had to show prejudice. Id. at 821-22.

In Apelt's case, the Arizona Supreme Court denied his claim, stating:

861 P.2d at 653.

None of the critical factors in McKinney are present in this case. In particular: (1) the trial court did not state a factual conclusion that any of Apelt's proffered mitigation failed to affect his conduct; (2) the Arizona Supreme Court did not state a factual conclusion that any of Apelt's proffered mitigation would have influenced him not to commit the crime; and (3) the Arizona Supreme Court did not cite Ross or Wallace when reviewing Apelt's mitigation evidence.

Moreover, Apelt's claim that the Arizona courts applied an unconstitutional causal nexus requirement is subject to AEDPA, and, accordingly, the state court's legal and factual determinations are entitled to deference. Apelt has not shown that the Arizona courts failed to follow established federal law because it appears that the Arizona Supreme Court did consider all the proffered mitigation evidence. We review state court decisions on the basis of established federal law as of the time of the state court's decision. See Greene v. Fisher, 565 U.S. 34, 38, 132 S.Ct. 38, 181 L.Ed.2d 336 (2011). Apelt also has not shown that the Arizona Supreme Court's determination is an unreasonable determination of the facts. Even if the Arizona Supreme Court's opinion could be construed as implicitly applying a causal nexus standard — which we doubt — Apelt has not shown that reasonable jurists could not conclude otherwise. See Richter, 562 U.S. at 101, 131 S.Ct. 770 (holding that federal habeas relief is precluded so long as fairminded jurists could disagree on the correctness of the state court decision).

Finally, even if Apelt had a stronger argument that the Arizona Supreme Court applied an unconstitutional causal nexus requirement, he has failed to make the requisite showing of prejudice required for federal habeas relief. The Supreme Court in Eddings, 455 U.S. at 114-15, 102 S.Ct. 869, held that although the states could not exclude mitigating evidence from consideration, they were entitled to determine the weight to be given mitigating evidence. See also Greenway v. Ryan, 866 F.3d 1094, 1100 (9th Cir. 2017) (per curiam) (stating "even if we were to determine that the state court did apply the causal-nexus test in violation of Eddings, there could have been no prejudice because the aggravating factors overwhelmingly outweighed all the evidence that Greenway asserted as mitigating"). In light of the overwhelming evidence supporting the aggravating factors, a reasonable jurist could conclude that whatever weight was afforded the limited proffered mitigation evidence, it would not be sufficient to call for leniency.26 Apelt has not shown that he is entitled to relief on his claim that the Arizona Supreme Court applied an unconstitutional causal nexus requirement, and the district court's denial of relief on this claim is affirmed.

2. Apelt's contention that trial counsel was ineffective because he failed to challenge Apelt's competency to be tried and sentenced is not persuasive.

Apelt correctly notes that the constitution prohibits the trial of an intellectually disabled person, see Cooper v. Oklahoma, 517 U.S. 348, 356, 116 S.Ct. 1373, 134 L.Ed.2d 498 (1996), and that to be competent to stand trial, a person must be able to consult with counsel with a reasonable degree of rational understanding. See Dusky v. United States, 362 U.S. 402, 402-03, 80 S.Ct. 788, 4 L.Ed.2d 824 (1960) (per curiam). Apelt further asserts that counsel is obligated to challenge his client's competency when there is reason to believe that the client may be incompetent, and that Arizona Rule of Criminal Procedure 11 provides a mechanism to seek a competency evaluation.

Apelt contends that his counsel's performance fell below the required standard under Strickland because Villarreal failed "to investigate or litigate Mr. Apelt's competency to stand trial, despite the wealth of evidence demonstrating Mr. Apelt suffered from a serious psychiatric disorder, was suicidal prior to trial, and was being administered medications known to have a dramatic effect on a patient's ability to interact with counsel and understand the proceedings." Apelt points out that Dr. Fisher testified that the drugs Apelt was given during his pre-trial incarceration were "generally considered to possess significant central nervous system (CNS) depressant effects." Apelt argues that because Villarreal knew, or should have known, of Apelt's over-medication, hospitalization, and placement under suicide watch while awaiting trial, he was ineffective in failing to investigate Apelt's competency to be tried and sentenced. Apelt further asserts that Villarreal had no strategy for not investigating Apelt's competence, and thus his performance fell below the minimum professional standard set forth in Strickland.

These claims of IAC are subject to AEDPA's standard of review.27 The district court found that "the record contains no support for the proposition that Apelt was not competent to stand trial." It notes that Villarreal did not neglect to consider Apelt's competence. Rather, co-counsel traveled to Germany before the trial but failed to find evidence that would support a motion to determine competency. Also, Apelt was actively involved in his defense and the trial proceedings. It appears that Apelt's behavior at trial and his testimony gave no cause for Villarreal to doubt his competence.28

In denying Apelt's claim of lack of competence to stand trial, the district court recognized that Apelt had been prescribed powerful drugs prior to and during his trial, but held that this fact in itself did not render him incompetent and that there was no evidence "that the drugs did in fact affect his competence." See Shan Wei Yu, 484 F.3d at 985. The district court similarly found that Apelt's placement on suicide watch and his history of mental health problems were not sufficient to show he was incompetent, particularly as he "failed to identify an instance in which he behaved irrationally, appeared not to understand the proceedings, or did not communicate effectively with Villarreal."

Apelt's claims turn not on whether he was, in fact, competent, but whether Villarreal was ineffective under the Strickland standard in failing to question Apelt's competence. In a federal habeas proceeding, a state court ruling on IAC is entitled to double deference. Pinholster, 563 U.S. at 189, 131 S.Ct. 1388. Our review of the record fails to disclose any incident or exchange that would have put Villarreal on notice that he should question Apelt's competency to stand trial. Even if Villarreal should have, but failed to, pay attention to Apelt's medication and treatment while incarcerated pending trial, this would not necessarily have raised questions of competency in light of Apelt's active and coherent involvement in the proceedings. Because we find that Apelt has not shown that the state courts unreasonably denied his claim of incompetence to stand trial, we affirm the district court's denial of relief on Apelt's claims that he was incompetent to stand trial or be sentenced.

IV.

It has been 29 years since Apelt murdered his wife of less than two months. We have carefully reviewed the briefs and records in this case and conclude that Apelt's federal habeas petition should be denied. We reject Arizona's arguments that we lack jurisdiction to consider Apelt's claim of ineffective assistance of counsel at sentencing, and we agree with the district court that Apelt was denied effective assistance of counsel at sentencing. However, we find that Apelt has failed to show that the state courts' determination that counsel's deficient performance was not prejudicial was unreasonable: there are reasonable arguments that the proffered additional mitigating evidence would not have changed Apelt's sentence. Accordingly, the district court's grant of the petition is vacated.

We reject all of Apelt's challenges to his conviction and sentence. He has not shown that, under the extant federal law at the time, the Arizona courts violated his constitutional rights by denying counsel funding to investigate mitigating evidence. See Caldwell, 472 U.S. at 323 n.1, 105 S.Ct. 2633; Williams, 441 F.3d at 1054. He has not shown that he is entitled to relief under Atkins because the record fairly supports the state courts' determination that he does not suffer from significant deficits in adaptive behavior. We have reviewed the Arizona Supreme Court's opinion pursuant to our en banc opinion in McKinney, 813 F.3d 798, and conclude that the court did not impose an unconstitutional causal nexus requirement when it affirmed Apelt's capital sentence. Finally, we conclude that Apelt has not shown that his counsel was ineffective in failing to question his competence to stand trial and be sentenced.

The district court's grant of the writ is vacated and Apelt's federal habeas petition is denied.