Cite as: 586 U. S. ____ (2019)           1

                        Per Curiam
                   SOTOMAYOR, J., dissenting

SUPREME COURT OF THE UNITED STATES
   DONNIE CLEVELAND LANCE v. ERIC SELLERS,
                 WARDEN
   ON PETITION FOR WRIT OF CERTIORARI TO THE UNITED
  STATES COURT OF APPEALS FOR THE ELEVENTH CIRCUIT
             No. 17–1382. Decided January 7, 2019

   The petition for a writ of certiorari is denied.
  JUSTICE SOTOMAYOR, with whom JUSTICE GINSBURG and
JUSTICE KAGAN join, dissenting from denial of certiorari.
   Before deciding that petitioner Donnie Cleveland Lance
should die as punishment for two murders he committed,
a jury heard no evidence whatsoever to counterbalance the
State’s case for the death penalty. Lance’s counsel bore
responsibility for the one-sidedness of the sentencing
proceedings; he inexcusably failed even to look into, much
less to put on, a case for sparing Lance’s life. And we have
since learned that Lance suffers from significant cognitive
impairments that the jury could have weighed in as-
sessing his moral culpability. In other words, there is a
meaningful case to be made for sparing Lance’s life, but—
because he lacked access to constitutionally adequate
counsel—he has never had a chance to present it.
   The Georgia Supreme Court concluded that this state of
affairs was constitutionally tolerable because, in its view,
Lance’s untold story stood no chance of persuading even a
single juror to favor life without parole over a death sen-
tence. The U. S. Court of Appeals for the Eleventh Circuit
held that its conclusion was not unreasonable. I cannot
agree. Our precedents clearly establish that Lance was
prejudiced by his inability to inform the jury about his
impairments. I therefore would grant Lance’s petition for
review and summarily reverse.
2                        LANCE v. SELLERS

                            Per Curiam
                       SOTOMAYOR, J., dissenting

                              I
                             A
  The facts of Lance’s crimes—murdering his ex-wife,
Sabrina “Joy” Lance, and her boyfriend, Dwight “Butch”
Wood, Jr., in 1997—admittedly inspire little sympathy.
Lance went to Butch’s home, kicked in the front door, shot
Butch with a shotgun, then bludgeoned Joy to death with
the gun. According to a fellow inmate, he later bragged
about the killings. Lance also had an extensive prior
history of domestic violence against Joy.1
  Due to his counsel’s ineffectiveness, however, those facts
were all the jurors ever learned about Lance; they heard
no evidence why his life was worth sparing. Lance was
represented during both the guilt and penalty phases of
his trial by a solo practitioner who became convinced of
Lance’s innocence—and his own ability to prove it—early
in the representation. He thus prepared exclusively for
the guilt-or-innocence phase of the trial. Counsel did not
even broach the subject of possible penalty-phase evidence
with Lance or his family, because he did not want them
“thinking that [he] might be thinking in terms of losing
the case.” App. to Pet. for Cert. 232. So when the jury
found Lance guilty and the question became whether
Lance should be put to death,2 Lance’s counsel had no
evidence whatsoever to present.
——————
  1 Lance previously had kidnapped Joy, electrocuted her, beaten her,

strangled her, and threatened her with various other harms. He also
repeatedly had threatened to kill her if she left him or became involved
with Butch. Four years earlier, Lance and a friend took a shotgun to
Butch’s home and kicked in the door, but fled when a child inside spoke
to them.
  2 The jury found that two aggravating circumstances supported

Lance’s eligibility for the death penalty: that he committed a double
murder and that Joy’s killing was “outrageously or wantonly vile,
horrible, or inhuman.” App. to Pet. for Cert. 74; Lance v. State, 

, 23, 

, 677 (2002); see also Ga. Code Ann. §§17–10–
30(b)(2), (b)(7) (Supp. 2018).
                     Cite as: 586 U. S. ____ (2019)                     3

                            Per Curiam
                       SOTOMAYOR, J., dissenting

   The State did. It called six witnesses, including the
victims’ relatives, to explain why Lance deserved to die.
The State’s closing argument emphasized Lance’s history
of violence against Joy, the brutality of her killing, and
Lance’s apparent lack of remorse. The State urged the
jury to perceive Lance as “ ‘cold and calculating’ ” and
repeatedly asked “ ‘what kind of person’ ” would do these
things. 1 App. in No. 16–15008 (CA11), pt. 1, pp. 68, 75,
77. Lance’s counsel, by contrast, made no opening state-
ment and presented no mitigating evidence. By his own
admission, he “had nothing to put on.” App. to Pet. for
Cert. 273. His closing argument merely urged the jury to
consider Lance’s family and to resist the temptation to
exact vengeance. About Lance, counsel said only that he
was “ ‘kind of a quiet person and a country boy’ ” who
“ ‘doesn’t talk a lot.’ ” 1 App. in No. 16–15008, pt. 1, at 85.
   The jury sentenced Lance to death.
                              B
   In 2003, Lance filed a petition for postconviction relief in
state court, asserting that his trial counsel’s failure to
investigate or present any mitigating evidence was inef-
fective assistance of counsel. Essentially, he argued that
there was a meaningful case to be made for sparing his
life, and that his counsel had forfeited his chance to do so
through inattention.
   The evidence showed that counsel could have found
possible cognitive problems had he looked into Lance’s
personal history. That history included repeated serious
head traumas caused by multiple car crashes, alcoholism,
and—most seriously—Lance’s once being shot in the head
by unknown assailants while lying on his couch.3 In the
——————
  3 In addition to the history discussed by the court, Lance also ingested
gasoline as a small child, was trampled by a horse as a teenager, and
once was overcome by fumes while working to clean the interior of an
oil tanker truck. 1 App. in No. 16–15008, pt. 2, pp. 202–203.
4                        LANCE v. SELLERS

                           Per Curiam
                      SOTOMAYOR, J., dissenting

aftermath of the shooting, Lance had “terrible headaches,”
“dizziness,” “difficulty working,” and “became even more
quiet than he had before.” App. to Pet. for Cert. 171–172.
The court found that any reasonable defense attorney
would have had Lance’s mental health evaluated and, in
so doing, uncovered “significant mitigating evidence for
the jury to consider.” 

   Four mental health professionals testified at an eviden-
tiary hearing.4 They agreed on many points. First, Lance
had permanent damage to his brain’s frontal lobe. Second,
his IQ placed him in the borderline range for intellectual
disability. Third, his symptoms warranted a diagnosis of
clinical dementia. The experts differed somewhat, however,
over the extent and practical consequences of Lance’s
brain damage. Primarily, the experts seemed to disagree
about the extent to which Lance’s brain damage affected
his impulse control.5
   The Superior Court granted Lance’s habeas petition and
vacated his death sentence, holding that trial counsel’s
failure to investigate and present evidence of Lance’s
mental condition was deficient performance, and that his
failure prejudiced Lance. The missing evidence could have

——————
    4 Lanceput on Thomas Hyde, an expert in behavioral neurology; Ri-
cardo Weinstein, an expert in neuropsychology; and David Pickar, an
expert in psychiatry and clinical neuroscience. The State called Daniel
Martell, an expert in neuropsychology. (A fifth expert’s unsworn report
was ruled inadmissible by the Georgia Supreme Court. See Hall v.
Lance, 

, 371, n. 1, 

, 815, n. 1 (2010).)
  5 Hyde, Weinstein, and Pickar opined that the type and extent of

damage reflected in Lance’s test results would adversely affect his
ability to suppress impulsive behavior. Weinstein and Hyde added that
the damage could impair Lance’s ability to conform his conduct to the
law, and Hyde noted that the effects of Lance’s impairments would be
most acute in moments of emotional stress. Martell, in contrast, saw
no direct evidence of impulse-control difficulties and opined that
Lance’s brain damage would not “ ‘prevent him’ ” from conforming his
conduct to the law. 1 App. in No. 16–15008, pt. 3, at 170.
                    Cite as: 586 U. S. ____ (2019)                  5

                           Per Curiam
                      SOTOMAYOR, J., dissenting

prompted a different sentence, the court explained, be-
cause it went directly to the key issue before the jury: the
assessment of Lance’s character, culpability, and worth.
  The Georgia Supreme Court, however, reversed and
reinstated Lance’s death sentence. Hall v. Lance, 

, 

(2010). It agreed that counsel’s
performance was deficient but held that Lance suffered no
prejudice. As relevant here, it held that even if the jury
had considered at trial all the neuropsychological evidence
adduced at the postconviction hearing, there was no rea-
sonable probability that Lance’s sentence would have
changed.6 In the Georgia Supreme Court’s view, the new
evidence was only “somewhat mitigating” because it
showed only “subtle neurological impairments,” which
would necessarily have been outweighed by Lance’s prior
threats and violence toward the victims, the nature of the
crime, and Lance’s statements and demeanor in its after-
math. 

687 S. E. 2d, at 815–816.
                            C
  Lance sought a federal writ of habeas corpus. The U. S.
District Court for the Northern District of Georgia denied
the petition but granted a certificate of appealability.
Under the deferential review provisions of the Antiterror-
ism and Effective Death Penalty Act of 1996, 

.
§2254(d), the U. S. Court of Appeals for the Eleventh
Circuit affirmed, holding that the Georgia Supreme
Court’s conclusion that the absence of the postconviction
mental health evidence caused Lance no prejudice “was
not unreasonable.” Lance v. Warden, 706 Fed. Appx. 565,
573 (2017).
——————
  6 As an alternative ground for finding no prejudice, the Georgia Su-

preme Court also hypothesized that even an adequate investigation
would not have uncovered the evidence that Lance presented at the
postconviction hearing. That conclusion is not implicated by Lance’s
petition because the Court of Appeals did not address it.
6                    LANCE v. SELLERS

                        Per Curiam
                   SOTOMAYOR, J., dissenting

                               II
   To prevail on a Sixth Amendment ineffective-assistance-
of-counsel claim, a defendant must show both that his
counsel’s performance was deficient and that his counsel’s
errors caused him prejudice. In assessing deficiency, a
court asks whether defense “counsel’s representation fell
below an objective standard of reasonableness.” Strick-
land v. Washington, 

, 688 (1984). To estab-
lish prejudice, a defendant must show “that there is a
reasonable probability that, but for counsel’s unprofes-
sional errors, the result of the proceeding would have been
different.” 

When, as here, a petitioner seeks
federal habeas review of a state court’s rejection of his
ineffective-assistance-of-counsel claim, he can prevail only
if the decision was “contrary to, or involved an unreason-
able application of,” Strickland and its progeny, or rested
“on an unreasonable determination of the facts in light of
the evidence presented in the State court proceeding.” 

. §2254(d).
   Because the Supreme Court of Georgia mischaracterized
or omitted key facts and improperly weighed the evidence,
I agree with Lance that its decision was an objectively
“unreasonable application of ” our precedents. §2254(d)(1);
see Wiggins v. Smith, 

, 528 (2003). I would
therefore grant the petition and summarily reverse.
                             A
   With regard to Strickland’s performance prong, the
Georgia Supreme Court determined that trial counsel’s
failure to investigate possible mitigation was deficient.
See 

, 687 S. E. 2d, at 812–813. That
is plainly correct. Counsel in a death penalty case has an
obligation at the very least to consider possible penalty-
phase defenses. See 

–522. By
his own admission, counsel here did not. Without any
inquiry into what penalty-phase evidence he might be
                     Cite as: 586 U. S. ____ (2019)                    7

                            Per Curiam
                       SOTOMAYOR, J., dissenting

forgoing, he succumbed to tunnel vision—and as a conse-
quence left Lance defenseless. Because nothing here
“obviate[d] the need for defense counsel to conduct some
sort of mitigation investigation,” Lance has satisfied
Strickland’s deficient-performance requirement. Porter v.
McCollum, 

, 40 (2009) ( per curiam); see also
Rompilla v. Beard, 

, 381 (2005); 

.
                             B
  Turning to the prejudice prong, the Court of Appeals
was wrong to conclude that Lance suffered no clearly
established prejudice from his inability to make his case.
Georgia law permits a death sentence only upon a unani-
mous jury recommendation, so Lance needed only to show
“a reasonable probability that at least one juror would
have struck a different balance” between the aggravating
and the mitigating factors had he or she considered the
missing evidence. 

; see Ga. Code
Ann. §§17–10–31(a), (c).7 The trial court, upon hearing
Lance’s proffered mitigation evidence, concluded that it
was “extremely important for the jury to consider” and
thus that its absence was prejudicial. App. to Pet. for
Cert. 174. Under any reasonable application of Strickland
and its progeny, that conclusion was correct. See 

. §2254(d); 

.
  To determine whether a defendant reasonably might
have been spared a death sentence but for his counsel’s
deficiency, courts take into account “the totality of the

——————
  7 In Georgia, “a sentence of death shall not be imposed unless the jury

verdict includes a finding of at least one statutory aggravating circum-
stance and a recommendation that such sentence be imposed.” Ga.
Code Ann. §17–10–31(a). “If the jury is unable to reach a unanimous
verdict as to sentence, the judge shall dismiss the jury and shall impose
a sentence of either life imprisonment or imprisonment for life without
parole.” §17–10–31(c).
8                    LANCE v. SELLERS

                        Per Curiam
                   SOTOMAYOR, J., dissenting

available mitigation evidence—both that adduced at trial,
and the evidence adduced in the habeas proceeding,” then
“reweigh it against the evidence in aggravation.” Williams
v. Taylor, 

, 397–398 (2000). “We do not
require a defendant to show that counsel’s deficient con-
duct more likely than not altered the outcome of his penalty
proceeding, but rather that he establish a probability
sufficient to undermine confidence in that outcome.”

(internal quotation marks and
alteration omitted).
  The jurors who sentenced Lance determined whether he
would live or die “knowing hardly anything about him
other than the facts of his crimes.” 

They heard
nothing “that would humanize [Lance] or allow them to
accurately gauge his moral culpability.” 

Yet if
counsel had performed his duties, the jurors would have
heard that Lance’s brain endured physical trauma
throughout his life, resulting in frontal lobe damage and
dementia. The jury further would have heard that Lance’s
IQ placed him within the borderline range for intellectual
disability. The jury also would have heard that Lance’s
cognitive deficits could affect his impulse control and
capacity to conform his behavior to the law, especially at
moments of emotional distress. Taken together, those
facts—with their accompanying explanatory potential to
humanize Lance, or at least to render less incomprehensi-
ble his conduct—were significant mitigating evidence. See

42–43 (noting the potentially mitigating effect of
evidence that the defendant “suffered from brain damage
that could manifest in impulsive, violent behavior” and
was “substantially impaired in his ability to conform his
conduct to the law”).
  To be sure, the evidence before the jury—the brutality of
Joy’s death, Lance’s past violence toward her, and Lance’s
conduct thereafter—could have supported a death sen-
tence. See Ga. Code Ann. §§17–10–30(b), 17–10–31(a).
                 Cite as: 586 U. S. ____ (2019)            9

                        Per Curiam
                   SOTOMAYOR, J., dissenting

But there is a stark contrast between no mitigation evi-
dence whatsoever and the significant neuropsychological
evidence that adequate counsel could have introduced as a
potential counterweight. Lance’s unintroduced case for
leniency, even if not airtight, “adds up to a mitigation case
that bears no relation to the few naked pleas for mercy
actually put before the jury.” 

;
see also 

. Our precedents thus
clearly establish Lance’s right to a new sentencing at
which a jury can, for the first time, weigh the evidence
both for and against death.
   The Georgia Supreme Court reached its contrary con-
clusion only by unreasonably disregarding or minimizing
Lance’s evidence. The state court acknowledged that
experts would testify that “ ‘significant damage’ ” to
Lance’s frontal lobe compromised his ability “ ‘to conform
his conduct to the requirements of the law.’ ” 

–371, 687 S. E. 2d, at 814. It failed, however, to
allow for the possibility that the jury might credit that
evidence. This Court previously has cautioned against
prematurely resolving disputes or unreasonably discount-
ing mitigating evidence in this context. See 

(“While the State’s experts identified perceived
problems with the tests [showing brain damage and cogni-
tive defects] and the conclusions [the defense expert] drew
from them, it was not reasonable to discount entirely the
effect that [the defense expert’s] testimony might have had
on the jury”). We should do so again here.
   Further, the Georgia Supreme Court relied on charac-
terizations of Lance’s evidence that cannot be squared
with the record, which “further highlights the unreason-
ableness of ” the Georgia Supreme Court’s decision. Wig-

; see 

. §2254(d)(2). With
regard to Lance’s frontal lobe damage, the Georgia Su-
preme Court appears to have credited the testimony of the
State’s expert over Lance’s experts’ testimony, treating as
10                        LANCE v. SELLERS

                            Per Curiam
                       SOTOMAYOR, J., dissenting

definitive Martell’s assertion that “Lance’s symptoms were
so subtle that a typical court-ordered evaluation might not
have given any indication of problems.” 

, 687 S. E. 2d, at 815; see also 

687 S. E. 2d,
at 816. Yet the other experts concluded that Lance’s
impairments and resulting behavioral distortions were
“serious” and “significant.”8 E.g., 1 App. in No. 16–15008,
pt. 3, at 92; 2 

The Georgia Supreme Court also
unreasonably dismissed the experts’ consensus that Lance
was in the borderline range for intellectual disability,9
and never mentioned—much less discussed the signifi-
cance of—Lance’s dementia diagnosis.
  These errors, taken together, make clear that the Geor-
gia Supreme Court applied our Strickland precedents in
an objectively unreasonable manner. The mental impair-
ment evidence reasonably could have affected at least one
juror’s assessment of whether Lance deserved to die for
his crimes, and Lance should have been given a chance to
make the case for his life. The Georgia Supreme Court’s
conclusion that it would be futile to allow him to do so was
unreasonable.

——————
   8 Moreover, it is unclear even that Martell’s milder characterizations

genuinely contradicted the other experts’ testimony. Unlike the other
experts, Martell seems at least sometimes to have been characterizing
Lance’s impairments “relative to his overall borderline [intellectually
disabled] baseline,” 1 App. in No. 16–15008, pt. 3, at 151, not relative to
the average person or to the level at which Lance might have func-
tioned absent his head traumas. Compare 2 

(Weinstein:
specific test results “vastly excee[d] the threshold for impairment” and
“indicate significant organic impairment of the frontal lobe”), with 2 

(Martell: results on the same test were “at a level expected for
[Lance’s] IQ” or “showed mild impairment”).
   9 See 

, 687 S. E. 2d, at 815 (describing Lance as

merely “in the lower range of normal intelligence”). But see, e.g., 1
App. in No. 16–15008, pt. 3, at 135 (Martell, describing Lance’s intellec-
tual functioning as “in the borderline range,” which is “lower than low
average”).
                 Cite as: 586 U. S. ____ (2019)         11

                       Per Curiam
                  SOTOMAYOR, J., dissenting

                           III
  Absent this Court’s intervention, Lance may well be
executed without any adequately informed jury having
decided his fate. Because the Court’s refusal to intervene
permits an egregious breakdown of basic procedural
safeguards to go unremedied, I respectfully dissent.