FOR PUBLICATION
 UNITED STATES COURT OF APPEALS
      FOR THE NINTH CIRCUIT

ROGER MARK SCOTT,                         No. 05-99012
             Petitioner-Appellant,
               v.                           D.C. No.
                                         CV-97-01554-PGR
DORA B. SCHRIRO,
                                            OPINION
            Respondent-Appellee.
                                     
       Appeal from the United States District Court
                for the District of Arizona
       Paul G. Rosenblatt, District Judge, Presiding

                   Argued and Submitted
         July 15, 2008—San Francisco, California

                    Filed June 2, 2009

  Before: Alex Kozinski, Chief Judge, Jerome Farris and
              Carlos T. Bea, Circuit Judges.

                   Per Curiam Opinion




                           6541
6544                 SCOTT v. SCHRIRO




                       COUNSEL

Jon M. Sands, Michael L. Burke, Jennifer Y. Garcia, Federal
Public Defender’s Office, Phoenix, Arizona, for the
petitioner-appellant.
                        SCOTT v. SCHRIRO                     6545
Terry Goddard, Kent Cattani, J.D. Nielsen, Office of the
Attorney General of Arizona, Capital Litigation Section,
Phoenix, Arizona, for the respondents-appellees.


                           OPINION

PER CURIAM:

   Roger Scott, an Arizona state prisoner sentenced to death,
appeals the denial of his petition for a writ of habeas corpus
in federal district court. When a state prisoner files such a
petition, the district court will usually not hear any claim the
petitioner did not first present to the state courts. This process
is referred to as the prisoner “exhausting” his state remedies.
Nor will the district court decide a claim denied by a state
court because the petitioner failed to follow a rule of state
procedure that is both adequate and independent of federal
law. To be considered “adequate,” the state rule must be one
that is consistently applied by the courts of that state in the
same manner it was applied to the current petitioner’s case.

   The dispositive issue in this case is whether the Arizona
Superior Court relied on an adequate state bar, consistently
applied, by the Arizona courts when it denied Scott’s state
petition for post-conviction relief. We conclude it did not. It
held Arizona Rule of Criminal Procedure 32.6(d) (“Rule
32.6(d)”) prohibited Scott from filing an amendment to his
previously-dismissed Arizona post-conviction petition for
relief. His amendment alleged Scott had suffered ineffective
assistance of counsel at his trial. In doing so, the post-
conviction court ignored Arizona precedent holding such a
petition could be so amended. See State v. Rodriguez, 

, 641 (Ariz. Ct. App. 1995) (holding a post-
conviction court has the authority under Rule 32.6(d) to allow
the filing of an amended petition upon a showing of good
cause, even after the court has already dismissed the first peti-
6546                    SCOTT v. SCHRIRO
tion). Scott’s first petition for post-conviction relief was filed
in 1995. Accordingly, the amended Rule 32.6(d) was not an
“adequate” state procedural rule that barred subsequent fed-
eral review of Scott’s ineffective assistance of counsel claims.
We will remand those claims for the district court to consider
in the first instance.

   We reverse the district court’s denial of Scott’s petition in
part and remand to the district court to hold an evidentiary
hearing and rule on the merits of these claims. We affirm the
district court’s ruling that Scott was not prejudiced solely by
his counsel’s failure to present a recommendation for leniency
from the victim’s father as mitigation evidence. Nevertheless,
on remand the district court should hold an evidentiary hear-
ing and consider whether the failure to present such a recom-
mendation from the victim’s father, combined with the failure
of Scott’s counsel to submit other mitigating evidence as dis-
cussed below, resulted in prejudice.

             I.   Facts and Procedural History

  This case stems from the premeditated murder of a four-
year-old named Christopher Milke. Christopher’s mother,
Debra Milke, her roommate James Styers, and Styers’s friend,
Roger Scott, were each tried separately for first-degree mur-
der, conspiracy to commit murder, kidnapping, and child
abuse. All were convicted.

   At Scott’s trial, he was represented by Roland Steinle. The
State’s theory of the case was that Scott, Styers, and Debra
Milke planned to kill Christopher to claim $5,000 from a life
insurance policy covering Christopher, which Debra had
taken out through her work. Scott was to receive $250. Scott
testified during trial that he was only a dupe, lured into help-
ing his friend Styers after the fact. However, Scott had given
a full confession to the police of his own role in the planning
and execution of the kidnapping and murder of Christopher.
Scott confessed he drove with Styers and Christopher out into
                             SCOTT v. SCHRIRO                            6547
the desert, where Styers shot Christopher. Scott led the police
to Christopher’s body, the firearm used to kill Christopher
(which was in Scott’s closet), and a pair of bloody shoes worn
by Styers when he shot Christopher.1

   After a jury trial, Scott was found guilty of first-degree
murder, conspiracy to commit murder, and kidnapping.2 The
relevant facts of the case are set forth in the Arizona Supreme
Court’s opinion affirming Scott’s conviction. State v. Scott,

, 795-96 (Ariz. 1993). The details of the facts
supporting the underlying conviction, horrible as they are, are
not important for purposes of this appeal. Scott does not con-
test his conviction; he contests only his sentence.

   Scott received the death penalty for the first-degree murder
charge, and consecutive terms of imprisonment totaling 47
years-to-life for the conspiracy and kidnapping charges. When
sentencing Scott, the trial judge found three statutory aggra-
vating factors:3 (1) Scott committed the murder as an accom-
plice for pecuniary gain; (2) the murder was “heinous” and
“depraved” because it was a senseless murder and the victim
was helpless; and (3) Scott was an adult and the victim was
under the age of fifteen. Ariz. Rev. Stat. § 13-703(F)(5), (6),
   1
     Because the defendants were each tried separately, we caution that the
facts recited herein relate only to the trial of Scott, and must not be consid-
ered by us or by other courts in the cases against James Styers and Debra
Milke.
   2
     Scott was also convicted of child abuse, but that conviction was over-
turned by the Arizona Supreme Court on direct appeal.
   3
     Under Arizona law as it existed at that time, the trial judge, not the
jury, determined whether aggravating circumstances existed. While this
fact might have been a ground for a successful appeal under Blakely v.
Washington, 

(2004)—indeed Scott’s counsel raised the issue
on direct appeal—Blakely does not apply retroactively to cases on collat-
eral review. Schardt v. Payne, 

, 1036 (9th Cir. 2005). Simi-
larly, this would have been a valid claim under Ring v. Arizona, 

(2002), but Ring also does not apply retroactively to cases on collat-
eral review. Schriro v. Summerlin, 

, 358 (2004). Scott was
tried and convicted in 1991.
6548                    SCOTT v. SCHRIRO
(9). The court also found four non-statutory mitigating cir-
cumstances: (1) Scott’s cooperation with the police in investi-
gating the crime; (2) his conduct while incarcerated and
during trial; (3) his “bond of love” with his mother; and
(4) his psychological history. However, the judge concluded
these mitigating factors did not outweigh the aggravating fac-
tors and imposed the death penalty.

   Scott’s conviction and sentence were affirmed on direct
appeal to the Arizona Supreme Court. 

.
That court found one additional mitigating factor: Scott’s lack
of any prior felony convictions. 

this addi-
tional factor to the mitigating factors found by the trial court,
the Arizona Supreme Court held the aggravating factors still
carried more weight and affirmed Scott’s death sentence. 

of re-weighing the evidence is allowed under
Arizona law. See State v. Gallegos, 

, 1117-18
(Ariz. 1994).

   During the Arizona post-conviction proceedings, Neil Bas-
sett initially represented Scott. Pursuant to Arizona law at the
time, the post-conviction court was the same Superior Court
where Scott’s trial was held. The same judge heard the pro-
ceedings. Bassett raised a single issue: whether Scott’s trial
counsel, Steinle, rendered ineffective assistance of counsel by
his failure to submit proper proof of the victim’s father’s rec-
ommendation for leniency at sentencing.

   Prior to its decision, Scott had written the Arizona post-
conviction court repeatedly, seeking to have the court replace
Bassett with new counsel. He told the court Bassett refused to
communicate with him. Scott even wrote the court, stating he
had fired Bassett. The court ignored Scott’s letters and did not
hold a hearing to determine whether Scott was seeking to rep-
resent himself or whether new counsel should be appointed.
Instead, the court summarily denied the petition for post-
conviction relief in a minute order. Scott then filed a formal
motion to represent himself, and Bassett filed a motion to
                       SCOTT v. SCHRIRO                   6549
withdraw and to allow new counsel an extension of time to
file a motion for rehearing or other filing. The court granted
Scott’s motion for an extension of time and appointed new
counsel, Rachel Yosha.

   The court gave Yosha 30 days, plus one extension, to make
her first filing in the case. Within the time allowed, Yosha
filed motions to vacate the denial of the petition for post-
conviction relief and for leave to file an amended petition
raising 23 additional claims. As good cause for Scott’s failure
to file all his proposed claims in his first petition, Yosha
argued Scott’s previous counsel, Bassett, had been ineffective
—a claim accepted by the post-conviction court when it
granted the motion for new counsel.

   Among the proposed claims in the amendment to his peti-
tion for post-conviction relief were claims that Scott’s trial
counsel, Steinle, provided Scott ineffective assistance of
counsel when Steinle failed to accept a plea bargain offer for
second-degree murder, even though Scott said he wanted to
accept the offer, and even though Steinle recognized the offer
was “the only viable way [for Scott] to avoid the death penal-
ty” given his confession. Rather than plead guilty to second-
degree murder, Scott went to trial and was found guilty of
first-degree murder, as his confession meant he would be. At
sentencing, Steinle also failed to present several mitigating
circumstances, including evidence of four traumatic head
injuries Scott had suffered, a brain scan showing Scott’s brain
had atrophied, evidence Scott suffered from seizures, as well
as evidence of the plea bargain offer, which Scott wanted to
accept but Steinle rejected.

  The motions filed by Yosha contained the legal and factual
bases for each claim Scott wished to make in the post-
conviction petition for relief. The post-conviction court
denied the motions, holding it had “no authority” under Ari-
zona Rule of Criminal Procedure 32.6(d) to allow the filing
6550                         SCOTT v. SCHRIRO
of an amended petition because the motion was filed after the
original petition had been denied.

   Following the post-conviction court’s denial, Scott filed a
petition for review with the Arizona Supreme Court seeking
review of denial of his petition for post-conviction relief and
the denial of his motion to amend his petition.4 Yosha
attached the proposed amended petition in the appendix to
Scott’s brief.5 The amended petition contained the 23 addi-
tional claims Scott sought to bring. The Arizona Supreme
Court summarily denied the petition without comment.

   Scott then filed a timely pro se petition for writ of habeas
corpus in federal court. He was appointed new counsel, who
filed an amended petition, raising many of the claims Scott
had raised both on direct appeal and in his amended petition
for post-conviction relief to the state courts. The district court
held the only claim Scott had exhausted in state court was the
one ruled on by the state post-conviction court on the merits
—that failure to present a recommendation for leniency by the
victim’s father, Mark Milke, constituted ineffective assistance
of counsel. The district court denied this claim on the merits.
The court held Scott’s other proposed claims, including his
ineffective assistance of counsel claims, were procedurally
barred from federal review because: (1) the state’s denial of
post-conviction relief was based on an adequate and indepen-
dent rule of state procedure; and (2) the claims stated in the
proposed petition for post-conviction relief had not been fairly
presented to the state courts, and thus they were not “exhaust-
ed” in state court.
  4
     Under Arizona law, cases involving a capital offense are appealed
directly to the Arizona Supreme Court, bypassing the Arizona Court of
Appeal. Ariz. R. Crim. P. 31.2(b).
   5
     In relevant part, Arizona Rule of Criminal Procedure Rule
32.9(c)(1)(iv) provides that in petitions for review in capital cases, “all ref-
erences to the record in the trial court shall be supported by an appendix,
with appropriate copies of the portions of the record which support the
petition.”
                          SCOTT v. SCHRIRO                 6551
   On appeal to this court, Scott contends the district court
erred when it held the following three additional ineffective
assistance of counsel claims were procedurally barred from
federal review: (1) Steinle rendered ineffective assistance of
counsel because he failed to challenge the voluntariness of
Scott’s statements to the police; (2) Steinle rendered ineffec-
tive assistance of counsel because he did not investigate and
present mitigating evidence of Scott’s mental deficiencies
during the sentencing phase; and (3) appellate counsel ren-
dered ineffective assistance of counsel because he failed to
challenge the trial court’s finding Scott committed the crime
for pecuniary gain.

                           II.   Analysis

   We review de novo a district court’s dismissal of a habeas
petition for procedural default based on a finding that: (1) the
state court’s denial of relief was based on adequate and inde-
pendent state rule of procedure or (2) the petitioner failed to
exhaust the claims in state court. Insyxiengmay v. Morgan,

, 665 (9th Cir. 2005).

A.        Procedural Default

     1.    Adequate and Independent State Procedural Bar

   [1] Normally, a habeas petitioner carries the burden on
appeal. Sometimes, however, the burden rests with the state.
“Procedural default is an affirmative defense, and the state
has the burden of showing that the default constitutes an ade-
quate and independent ground” for denying relief. Insyxieng-

(emphasis added). Once the state meets
that burden of proof, the burden on all remaining issues shifts
to the petitioner.

  [2] To constitute an adequate and independent state proce-
dural ground sufficient to support a state court’s finding of
procedural default, “a state rule must be clear, consistently
6552                   SCOTT v. SCHRIRO
applied, and well-established at the time of petitioner’s pur-
ported default.” Lambright v. Stewart, 

, 1203
(9th Cir. 2001) (citations omitted) (emphasis added). A state
rule is considered consistently applied and well-established if
the state courts follow it in the “vast majority of cases.” See
Dugger v. Adams, 

, 411 n.6 (1989). We find the
State has not met its burden to prove the rule cited and relied
upon by the Arizona post-conviction court—Arizona Rule of
Criminal Procedure 32.6(d)—was clear, consistently applied,
and well-established at the time the post-conviction court
applied it to Scott’s case.

   The basis for the state court’s order denying Scott’s
motions to vacate the denial of the first petition and allow the
filing of an amended petition raising new grounds for relief
was as follows:

    There is little doubt that this Court is Authorized
    [sic], upon a showing of good cause, to permit a
    defendant to amend a petition for post-conviction
    relief before a dispositive order issues. See Rule
    32.6(d), A.R.Crim. P. Here, however, Defendant
    seeks an order vacating this Court’s order dismissing
    his Petition for Post-Conviction Relief. . . . To grant
    the relief requested by Defendant would be contrary
    to the underlying purpose of Rule 32 and inconsis-
    tent with its procedures.

   [3] This language implies the court thought that, regardless
whether Scott had shown good cause to excuse his failure to
plead all his claims in his first petition for post-conviction
relief, the court simply did not have authority to allow amend-
ment to the petition because it was amended after the court
had already denied his first petition. This conclusion is con-
trary to the plain language of Rule 32.6(d), which at the time
of Scott’s post-conviction proceeding read:
                           SCOTT v. SCHRIRO                        6553
      After the filing of a post-conviction relief petition,
      no amendments shall be permitted except by leave of
      court upon a showing of good cause.

Ariz. R. Crim. P. 32.6(d) (1996) (emphasis added). The only
condition to amendment of a filed petition is the existence of
good cause. Whether a court has or has not ruled on the origi-
nal petition is not mentioned as a condition to amendment.

   [4] The post-conviction relief judge conducted no analysis
as to whether Scott had shown good cause to amend his peti-
tion. Rather, it appears the judge relied on an earlier version
of Rule 32.6(d), which prohibited a post-conviction court
from allowing the filing of an amended petition after the first
petition had been dismissed. Before 1992, Rule 32.6(d) read,
“Amendments to pleadings shall be liberally allowed at all
stages of the proceeding prior to entry of judgment.” Ariz. R.
Crim. P. 32.6(d) (1991) (emphasis added).6 The emphasized
language from this prior version of the rule, restricting
amendments to the time period “prior to entry of judgment,”
was deleted by the legislature in 1992. Scott filed his pro-
posed amendment in 1996.

   The Arizona courts have not consistently interpreted the
1996 version of Rule 32.6(d) to prohibit amended or supple-
mental petitions for post-conviction relief when such amend-
ments or supplements are filed after the denial of the first
petition. To the contrary, before the post-conviction court’s
ruling in this case but after Rule 32.6(d) was amended in
1992, the Arizona Court of Appeals ruled in 1995 that a post-
conviction court has the authority to allow the filing of an
  6
   Arizona courts continue to construe Rule 32.6(d) as liberally allowing
amendments, even though this language was also deleted in the 1992 revi-
sions. See Canion v. Cole, 

, 1264 (Ariz. 2005) (holding
“Rule 32.6(d), which permits a defendant to amend his petition ‘upon a
showing of good cause,’ adopts a liberal policy toward amendment of
[post-conviction relief] pleadings.”).
6554                        SCOTT v. SCHRIRO
amended petition upon a showing of good cause, even if the
court has already dismissed the original petition. See Rodri-

(holding that good cause was shown
under Rule 32.6 where a petitioner sought to file a petition pro
se after the post-conviction court dismissed his first petition
because his post-conviction counsel failed to file the neces-
sary brief explaining is claims in a timely manner). Thus,
Rodriguez, the only published case that had interpreted Rule
32.6(d) after the 1992 amendment but before Scott’s proceed-
ing in 1996, was contrary to the post-conviction court’s ruling
in this case.7

   The Rodriguez case shows the post-conviction court did not
rely on a rule of state procedure that is regularly followed or
“consistently applied” by the Arizona state courts. As this
court has held, “federal courts should not insist upon a peti-
tioner, as a procedural prerequisite to obtaining federal relief,
complying with a rule the state itself does not consistently
enforce.” Siripongs v. Calderon, 

, 1318 (9th Cir.
1994).

   [5] Thus, given that neither the text of the 1992 version of
Rule 32.6(d) nor any case construing that version of the rule
state that a post-conviction court cannot grant a motion to
amend the petition after the original petition has been dis-
missed, the state has not met its burden of proving Rule
32.6(d) is consistently interpreted as it was interpreted here.
Accordingly, the district court erred in holding that Rule
32.6(d) constitutes an adequate and independent state proce-
  7
    Because the relevant inquiry is whether the rule was well-established
or consistently applied “at the time of [the] alleged default to bar federal
review,” cases decided after the purported procedural default normally
should normally not be considered. See 

, n.2.
Nevertheless, we note that after Scott’s trial, the Arizona Supreme Court
followed the reasoning of Rodriguez and issued orders allowing defen-
dants upon a showing of good cause to file amended or supplemental peti-
tions after their first petitions had been denied. See Arizona v. Stokley, No.
CV-97-0203-SA (1999); Arizona v. Kayer, No. CR-94-0694 (1998).
                        SCOTT v. SCHRIRO                     6555
dural bar to federal review on the merits and failing to rule on
the merits of the proposed claims.

  2.   Exhaustion

   [6] The district court held Scott did not exhaust his claims
of ineffective assistance of counsel because he failed to pres-
ent those claims to the Arizona courts. A federal court may
not grant habeas relief to a state prisoner unless the prisoner
has first exhausted his state court remedies. See 28 U.S.C.
§ 2254(b)(1). A petitioner satisfies the exhaustion requirement
by fully and fairly presenting each claim to the highest state
court. See 

. A petitioner fully
and fairly presents a claim to the state courts if he presents the
claim (1) to the correct forum, see § 2254(c); (2) through the
proper vehicle, see Castille v. Peoples, 

, 351
(1989); and (3) by providing the factual and legal basis for the
claim, see Weaver v. Thompson, 

, 364 (9th Cir.
1999). Full and fair presentation additionally requires a peti-
tioner to present the substance of his claim to the state courts,
including a reference to a federal constitutional guarantee and
a statement of facts that entitle the petitioner to relief. See
Picard v. Connor, 

, 278 (1971).

   Scott included his ineffective assistance of counsel claims
in the appendix of his petition for review to the Arizona
Supreme Court. He explicitly referenced his right to effective
assistance of counsel under the Sixth Amendment of the
United States Constitution. He also stated the operative facts
on which each of the claims were based and cited federal case
law to support his arguments. The only issue the state contests
is whether including the claims in an appendix in a petition
for review to the Arizona Supreme Court satisfied the fair pre-
sentation requirement for purposes of exhaustion. This is an
issue of federal law, not state law. We hold Scott did accom-
plish a full and fair presentation of his claims to the Arizona
Supreme Court. Scott included a copy of the amended petition
for post-conviction relief he sought to file in the post-
6556                       SCOTT v. SCHRIRO
conviction court in the Appendix to his petition for review
filed with the Arizona Supreme Court.

   [7] This case is indistinguishable from Insyxiengmay,
which held that presentation of an issue in an appendix is suf-
ficient to present the issue in a full and fair manner to the state
courts.8 See 

. Indeed, it is ques-
tionable whether the claims even needed to be presented in
the appendix to preserve them. As the Insyxiengmay court
noted,

      [W]e question whether in order to exhaust the three
      claims it was even necessary for Insyxiengmay to
      file an appendix with the Washington Supreme
      Court . . . . Because in his motion Insyxiengmay
      asked the Washington Supreme Court to allow the
      claims to proceed in the court of appeals, and the
      court declined the request, thus barring him from
      presenting the claims for review either to the court
      of appeals or the supreme court, any further duty to
      exhaust was excused.

n.5.

   Similarly, Scott petitioned the Arizona Supreme Court to
allow his claims to proceed in the post-conviction court and
he gave the court a copy of the amended petition he sought
to file, which included the operative facts and law. Thus, the
Arizona Supreme Court knew exactly which claims Scott
sought to present. The Arizona Supreme Court denied the
request, “thus barring him from presenting the claims for
review either to the [post-conviction court] or the supreme
court.” See 

further duty Scott had to
exhaust was excused.
  8
    The State argues Insyxiengmay is distinguishable because the decision
is based on Washington law but neither Arizona case law nor statutes hold
that issues are waived in post-conviction proceedings if they are raised
only in an appendix to a petition for review.
                        SCOTT v. SCHRIRO                    6557
   [8] All exhaustion requires is that the state courts have the
opportunity to remedy an error, not that they actually took
advantage of the opportunity. See Picard v. Connor, 

, 275 (1971). Accordingly, Scott exhausted his state reme-
dies with respect to the claims he sought to bring in his
amended petition for post-conviction relief.

  [9] We thus conclude Scott’s claims are not procedurally
barred from federal review.

  3.   Proceedings on Remand

   [10] “Where a petitioner raises a colorable claim [to relief],
and where there has not been a state or federal hearing on this
claim, we must remand to the district court for an evidentiary
hearing.” Phillips v. Woodford, 

, 973 (9th Cir.
2001) (quoting Smith v. McCormick, 

, 1170
(9th Cir. 1990)).

   [11] The most serious claim Scott brings is ineffective
assistance of counsel for failure to present mitigating evidence
of his mental deficiencies at his sentencing hearing. The
record reflects Steinle, the State, and the trial judge all knew
Scott claimed he had “brain shrinkage” caused by several
traumatic brain injuries, including a bicycle accident in sev-
enth grade with a car, two motorcycle accidents, and a car
accident, all of which had rendered Scott temporarily uncon-
scious. In fact, Steinle had used Scott’s claim of brain shrink-
age as grounds for requesting a pre-trial competency
evaluation ordered by the court. There is no evidence, how-
ever, Steinle independently investigated these claims to pres-
ent them as mitigating evidence in the penalty phase of the
trial.

   In Summerlin v. Schriro, 

, 631 (9th Cir. 2005),
this court granted an Arizona state petitioner’s habeas peti-
tion. Summerlin’s attorney never investigated or developed
evidence of Summerlin’s mental health history for presenta-
6558                    SCOTT v. SCHRIRO
tion at the penalty phase of his capital trial, even though coun-
sel knew he had been diagnosed with paranoid schizophrenia
and treated with anti-psychotic medication. In Summerlin, as
here, “[t]he strong psychiatric evidence of Summerlin’s lack
of impulse and emotional control and organic brain dysfunc-
tion could have provided significant mitigating evidence.” 

(emphasis added).

   As indicated by the 2006 report ordered by Scott’s federal
habeas attorneys, investigation would have revealed a com-
puter tomography (“CT”) scan demonstrating Scott had
organic brain damage. Scott’s organic brain injury is also
described in a psychiatric evaluation ordered by his federal
habeas attorneys in 1996. The report states a CT scan per-
formed in 1987 showed the presence of brain atrophy unusual
for a person of Scott’s age at the time, and Dr. Don, the psy-
chiatrist, linked this brain damage to a likelihood that Scott
was more easily influenced by Styers than would have been
a normal person.

   [12] Additionally, for several years Scott was a severe alco-
holic, drinking two fifths of whiskey every day—which may
also have contributed to cognitive problems. The trial court
refused to consider Scott’s alcoholism as a mitigating factor
because it was a voluntary act. This is contrary to Arizona
law. “Voluntary intoxication or substance abuse can be a miti-
gating factor. . . . Intelligence also has been considered as part
of determining whether a head injury caused damage suffi-
cient to warrant consideration as a mitigating factor.” State v.
Kayer, 

, 45, 47 (Ariz. 1999) (citing State v. Stok-
ley, 

, 469 (1995)). Certainly Scott’s traumatic
head injuries should have been, at the very least, investigated
by Steinle in preparation for the presentation of Scott’s
penalty-phase case by ordering the same hospital records
relied upon by the 2006 report. Such an omission by Steinle
is striking.

   It is also clear from the record that the State made a plea
offer to Scott before trial. According to Steinle’s affidavit,
                        SCOTT v. SCHRIRO                      6559
“[t]he state of Arizona indicated that if Mr. Scott agreed to
testify and was truthful in his testimony he could plead guilty
to second-degree murder.” However, according to Steinle’s
affidavit, Steinle rejected the offer because Scott would not
read it, despite the fact Scott wanted to accept the offer.
Regardless of the propriety of rejecting the plea offer on this
basis (which is highly suspect), evidence of the plea offer
could have been introduced during the sentencing phase as
mitigation. See 

(holding that evi-
dence the prosecution offered to allow the defendant to plead
guilty to second-degree murder and aggravated assault was
mitigating evidence that could be admitted in the sentencing
phase after the defendant had been found guilty of first-degree
murder). The plea offer’s mitigatory effect is clear: the prose-
cution thought this was not a clear-cut death penalty case.

.

   No court has weighed all of the mitigating evidence found
by the trial court as well as the additional factor—lack of
prior felony convictions—found by the Arizona Supreme
Court against the aggravating factors found at trial. In addi-
tion, Scott raised a further claim before the Arizona Supreme
Court and the district court—that his appellate attorney ren-
dered ineffective assistance of counsel because he did not
challenge the jury’s finding that he committed the crime for
pecuniary gain. If this claim is found to have merit, it will
mean there is one less aggravating factor to weigh in the
equation. Thus, it is possible that had Scott’s counsel pres-
ented this additional evidence during sentencing, Scott might
have received the lesser sentence of life without the possibil-
ity of parole. We remand to the district court to make that
determination.

  [13] Because Scott was never given a hearing in the state
court on his ineffective assistance of counsel claims, he is
entitled to a hearing in district court. 

.
On remand, the district court should hold an evidentiary hear-
6560                    SCOTT v. SCHRIRO
ing to allow both parties to put on evidence regarding each of
Scott’s claims of ineffective assistance of counsel.

   On remand, the district court should decide these issues de
novo after an evidentiary hearing because there is no state
court determination on the merits to which the district court
can defer. See Pirtle v. Morgan, 

, 1167-68 &
n.4 (9th Cir. 2002) (holding that where “there is no state court
decision on this issue to which to accord deference . . . con-
cerns about comity and federalism that arise when a state
court reaches the merits of a petition for post-conviction relief
do not exist [and] when it is clear that a state court has not
reached the merits of a properly raised issue, we must review
it de novo.”).

B.     Victim’s Father’s Leniency Recommendation

   Scott raises one claim that was decided on the merits in
both the state court and the federal district court: whether
Steinle’s failure to present the victim’s father’s recommenda-
tion Scott be given leniency at sentencing constituted ineffec-
tive assistance of counsel in violation of the Sixth
Amendment to the U.S. Constitution.

   [14] A criminal defendant is entitled to relief for ineffective
assistance of counsel when “counsel’s conduct so undermined
the proper functioning of the adversarial process that the trial
cannot be relied on as having produced a just result.” Strick-
land v. Washington, 

, 686 (1984). To establish
ineffective assistance, the defendant must show (1) counsel
made errors “so serious that counsel was not functioning as
the ‘counsel’ guaranteed by the Sixth Amendment,” and (2)
this deficient performance prejudiced the defense. 

To demonstrate prejudice, the defendant must show “there is
a reasonable probability that, but for counsel’s unprofessional
errors, the result of the proceedings would have been differ-
ent. A reasonable probability is a probability sufficient to
undermine confidence in the outcome.” 

In an
                        SCOTT v. SCHRIRO                      6561
appeal of a death sentence, it is not enough that the error may
have affected the outcome; the question is whether, “absent
the errors, the sentencer . . . would have concluded that the
balance of aggravating and mitigating circumstances did not
warrant death.” 

The ultimate inquiry “must be on
the fundamental fairness of the proceedings whose result is
being challenged.” 

   Because Scott filed his federal petition for writ of habeas
corpus on July 25. 1997, the merits of his claim are governed
by the Antiterrorism and Effective Death Penalty Act of 1996
(“AEDPA”). Under AEDPA, “it is not enough to convince a
federal habeas court that, in its independent judgment, the
state-court decision applied Strickland incorrectly.” Bell v.
Cone, 

, 699 (2002). Rather, a federal court may
grant habeas relief only when the state court’s adjudication on
the merits resulted in a decision that was “contrary to, or
involved an unreasonable application of,” Strickland or was
“based on an unreasonable determination of the facts in light
of the evidence presented in the State court proceeding.” 28
U.S.C. § 2254(d)(1) & (2).

   [15] We cannot perceive any strategic reason for Steinle’s
decision not to investigate or introduce any evidence that the
victim’s father, Mark Milke, recommended Scott not be given
the death penalty. See Correll v. Ryan, 

, 949 (9th
Cir. 2008) (“An uninformed strategy is not a reasoned strat-
egy. It is, in fact, no strategy at all.”). Indeed, in an affidavit
from Steinle filed during post-conviction proceedings, he does
not even mention investigating Milke’s recommendation that
Scott be shown mercy. Nowhere in the record does Steinle
provide a rationale for his decision not to introduce indepen-
dent evidence of Milke’s leniency recommendation.

   [16] Because Steinle had a duty to investigate and present
all reasonable mitigating evidence, his performance was not
reasonable “under prevailing professional norms.” See Wig-
6562                   SCOTT v. SCHRIRO
gins v. Smith, 

, 521 (2003); 

.

   It is not reasonably probable, however, that Milke’s
leniency recommendation would have changed Scott’s sen-
tence from death to life in prison. Milke’s leniency recom-
mendation is a non-statutory mitigating factor. See Ariz. Rev.
Stat. § 13-703(g). As the Arizona Supreme Court has recog-
nized, “[B]ecause a trial court has discretion in determining
how much weight to give each mitigating circumstance, non-
statutory mitigating circumstances might not be entitled to
much weight either individually or cumulatively.” 

.

   Here, the Arizona post-conviction judge who determined
this error was harmless was the same judge who sentenced
Scott. We know that at some point prior to imposing sentence
this judge considered and rejected the victim’s father’s recom-
mendation for leniency as he had read the pre-sentence report,
which contained a leniency recommendation by Mark Milke.
The judge must have determined the leniency recommenda-
tion did not carry much weight in light of the aggravating fac-
tors.

   [17] Ultimately, pursuant to AEDPA, we must give defer-
ence to a state court’s decision unless it is objectively unrea-
sonable. See 28 U.S.C. § 2254(d)(1); 

.
Because it is not reasonably probable that Scott’s sentence
would have changed had the leniency recommendation been
introduced by itself as mitigating evidence, the Arizona post-
conviction court’s determination Scott suffered no prejudice
was neither “contrary to” nor did it “involve an unreasonable
application of” Strickland. 28 U.S.C. § 2254(d)(1). Thus, this
claim does not entitle Scott to habeas relief.

   [18] However, this does not put the issue to rest. Among
the three ineffective assistance of counsel claims the district
court will consider on remand is that trial counsel was consti-
                          SCOTT v. SCHRIRO                       6563
tutionally ineffective because he did not investigate and pres-
ent mitigating evidence during the sentencing phase of Scott’s
trial. Thus, although the failure to present Milke’s recommen-
dation for leniency does not, by itself, establish prejudice, this
failure should be re-evaluated by the district court in light of
the other mitigating evidence counsel failed to present.

                        III.    Conclusion

   With respect to the following ineffective assistance of
counsel claims, we reverse the district court’s determination
because the claims are not procedurally defaulted and were
exhausted: (1) that trial counsel rendered ineffective assis-
tance of counsel because he failed to challenge the voluntari-
ness of Scott’s statements to the police; (2) that trial counsel
rendered ineffective assistance of counsel because he did not
investigate and present mitigating evidence of Scott’s trau-
matic brain injuries and their effect on his mental processes
during the sentencing phase; and (3) that appellate counsel
rendered ineffective assistance of counsel because he failed to
challenge the trial court’s finding Scott committed the crime
for pecuniary gain. We remand those claims to the district
court for a resolution on the merits in the first instance. We
affirm the district court’s denial on the merits of Scott’s claim
that his trial counsel was constitutionally ineffective for not
presenting a recommendation for leniency from the victim’s
father as mitigation evidence. Nevertheless, the district court
should reconsider whether this failure prejudiced Scott in light
of the other factors the district court considers on remand.

  Appellant is awarded costs.9

 AFFIRMED IN PART, REVERSED IN PART AND
REMANDED.
  9
   Appellee’s motion to file a supplemental brief is granted. The Clerk
shall file the brief received on August 1, 2008.