                 FOR PUBLICATION
 UNITED STATES COURT OF APPEALS
      FOR THE NINTH CIRCUIT

JOE LEONARD LAMBRIGHT,                    No. 04-99010
             Petitioner-Appellant,           D.C. No.
               v.                        CV-87-00235-TUC-
                                               JMR
DORA B. SCHRIRO, Director of
Arizona Department of                       ORDER
Corrections,                               AMENDING
             Respondent-Appellee.         OPINION AND
                                            AMENDED
                                            OPINION

       Appeal from the United States District Court
                for the District of Arizona
         John M. Roll, District Judge, Presiding

                  Argued and Submitted
           April 3, 2007—Pasadena, California

                   Filed May 11, 2007
                  Amended July 2, 2007

    Before: Warren J. Ferguson, Stephen Reinhardt, and
            David R. Thompson, Circuit Judges.

                 Per Curiam Opinion;
             Concurrence by Judge Ferguson




                           7727
                     LAMBRIGHT v. SCHRIRO                7731


                         COUNSEL

Jon M. Sands, Federal Public Defender, Dale A. Baich and
Jennifer Y. Garcia, Assistant Federal Public Defenders, Phoe-
nix,Arizona, for the petitioner-appellant.

Terry Goddard, Attorney General of the State of Arizona,
Kent E. Cattani, Chief Counsel, Capital Litigation Section,
and Patricia A. Nigro, Assistant Attorney General, Capital
Litigation Section, Phoenix, Arizona, for the respondant-
appellee.


                          ORDER

  The per curiam opinion filed May 11, 2007 is hereby
amended as follows:

1.   At page 5476, line 15 of the slip opinion, the word “few”
     is changed to “number of.”

2.   At page 5495, line 34 of the slip opinion, the word “few”
     is changed to “number of.”
7732                 LAMBRIGHT v. SCHRIRO
  With these amendments, Judges Ferguson, Reinhardt, and
Thompson vote to deny the petition for rehearing.

   Judge Reinhardt votes to deny the petition for rehearing en
banc; Judges Ferguson and Thompson so recommend. The
full court was advised of the suggestion for rehearing en banc.
No judge requested a vote on whether to rehear the matter en
banc. Fed. R. App. P. 35.

  The petition for rehearing and petition for rehearing en
banc are DENIED.

  No future petitions for rehearing or rehearing en banc will
be entertained.


                          OPINION

PER CURIAM:

   In this pre-AEDPA habeas appeal, we confront once again
the question whether defense counsel’s performance during
the sentencing phase of a capital trial was so deficient as to
violate the defendant’s right to counsel under the Sixth
Amendment. In March of 1982, Appellant Joe Leonard Lam-
bright and his co-defendant Robert Smith were convicted of
first degree murder, kidnapping, and sexual assault. After a
brief sentencing proceeding, Lambright was sentenced to
death. His conviction and sentence were affirmed by the Ari-
zona courts on direct appeal and in state post-conviction pro-
ceedings. Lambright then filed a habeas petition in federal
district court seeking reversal on various grounds. The district
court denied the petition, and Lambright appealed. In 1999,
we reversed his conviction on the ground that the use of dual
juries for a single trial of both Lambright and Smith violated
due process. The en banc court then reheard the case, reversed
the panel decision, and affirmed the denial of habeas relief
                         LAMBRIGHT v. SCHRIRO                         7733
with respect to the dual jury issue. After the case was returned
to the panel for resolution of Lambright’s remaining claims,
we rejected all of his contentions with the exception of pen-
alty phase ineffective assistance of counsel. With respect to
that issue, we remanded to the district court for an evidentiary
hearing. After the evidentiary hearing, the district court ruled
that Lambright’s trial counsel had not provided deficient rep-
resentation, and further ruled that even if the performance was
deficient, Lambright was not prejudiced thereby. Because we
conclude that trial counsel’s performance was both deficient
and prejudicial, we reverse and remand for issuance of a writ
of habeas corpus and a new sentencing proceeding.

      FACTUAL AND PROCEDURAL BACKGROUND

   In March of 1980, Lambright and Smith were traveling
across the country with Lambright’s girlfriend, Kathy Fore-
man. According to Foreman, who testified against Smith and
Lambright in exchange for immunity, Smith complained to
Lambright about the fact that he did not have a traveling com-
panion with whom he could engage in sexual relations. In
response, Lambright said they would find him a girl. Lam-
bright also said that “he would like to kill somebody just to
see if he could do it.” While passing through the Tucson, Ari-
zona area, the trio encountered a hitchhiker, Sandra Owen,
and offered her a ride. Owen accepted, got in the car, and the
four drove off. Smith raped Owen in the back seat of the car
on the way to a mountain site where they all exited the vehi-
cle. Smith then raped Owen a second time and thereafter
began choking her. Lambright then stabbed Owen numerous
times while Smith and Foreman restrained her. Finally, Lam-
bright struck Owen in the head with a rock. Owen died as a
result of her injuries.1
  1
   A fuller description of these events appears in our earlier en banc opin-
ion. Lambright v. Stewart, 191 F.3d 1181 (9th Cir. 1999).
7734                 LAMBRIGHT v. SCHRIRO
  After the trio was arrested, Lambright admitted involve-
ment in the offense, but told the police that Smith was the one
who murdered Owen. Smith told police that Foreman and
Lambright committed the murder. Foreman turned state’s evi-
dence and testified that Lambright and Smith were the real
culprits. On March 30, 1982, both Lambright and Smith were
convicted of first degree murder, sexual assault, and kidnap-
ping. The state sought and obtained the death penalty for both.

I.   Trial Counsel’s Penalty Phase Investigation

   At both the guilt and penalty phases of his trial, Lambright
was represented by attorney Carmine Brogna. Between Lam-
bright’s conviction and the sentencing hearing, Brogna met
with Lambright once for a little over an hour and spoke with
him once briefly over the phone. He spent less than an hour
reviewing the pre-sentence report and speaking with Lam-
bright’s probation officer, and a total of three hours drafting
and dictating the brief sentencing memorandum he submitted
to the court and the subpoena he used for the appearance of
his sole penalty phase witness, a guard at the jail in which
Lambright was being held.

   Although prior to sentencing Brogna became aware of
Lambright’s long history of mental health problems, his two
prior suicide attempts, and his resultant hospitalization in a
psychiatric facility, Brogna did not discuss these matters with
Lambright’s friends or family members, nor did he request
Lambright’s medical or hospital records. Moreover, although
he knew that Lambright had discussed traumatic combat
experiences in Vietnam with the probation officer assigned to
prepare a pre-sentence report and with the Pima County
Court’s psychologist, he did not attempt to obtain any infor-
mation about Lambright’s experiences in Vietnam nor their
effect on him. Even after the court’s psychologist drafted a
report in which he concluded that Lambright suffered from
antisocial personality disorder, Brogna did not contact the
                     LAMBRIGHT v. SCHRIRO                   7735
psychologist to discuss this diagnosis, nor did he attempt to
have another psychologist or psychiatrist evaluate Lambright.

   Brogna also knew that Lambright had a serious drug prob-
lem, but did no investigation with respect to the extent of his
drug use or its effect on his mental state or behavior. He like-
wise did not seek to obtain Lambright’s school or military
records. Nor did he contact either of Lambright’s former
wives. Although Brogna traveled with counsel for Lam-
bright’s co-defendant to Texas and Louisiana for five days
and spoke with a number of potential witnesses prior to the
guilt phase of Lambright’s trial, the trip did not yield any use-
ful mitigating evidence, and Brogna did no additional investi-
gating thereafter. It is unclear whether Brogna sought
information for use at the penalty phase proceeding from any
of the people he spoke with during this trip. Although Brogna
did speak to Lambright’s sister when he was in Texas, he
asked her primarily about Lambright’s conduct around the
time of the crime, and he does not recall whether he even
raised the issues of Lambright’s upbringing, mental health,
drug abuse, or any other potential mitigating factors.

II.   Presentation of Mitigating and Aggravating Evidence

    The sum total of the mitigating evidence that Brogna
offered at sentencing comprises less than three pages of a
double-spaced transcript, and all of it related solely to Lam-
bright’s conduct in jail. Although, as noted above, Brogna
knew that there were indications that Lambright was mentally
ill, Brogna failed to present any mitigating psychiatric or psy-
chological testimony. Nor did he call any of Lambright’s fam-
ily members or friends to testify about his unfortunate
childhood, his history of mental instability, his suicide
attempts, or his long-term drug abuse. Instead, Brogna prom-
ised the court that he had “one witness who will be very
brief.” The sole witness called by Brogna was George Din-
nen, an officer at the Pima County Jail, who testified that in
the six months in which he had supervised Lambright, there
7736                 LAMBRIGHT v. SCHRIRO
had been no “problems with him” and that he had “always
been respectful, courteous, and cooperative.” In addition to
calling this witness, Brogna submitted a two-and-a-half-page
legal memorandum listing various potentially mitigating cir-
cumstances, including (1) the fact that a deal was cut with
Lambright’s accomplice, Kathy Foreman, in exchange for her
cooperation with the prosecution, (2) Lambright’s “lack of a
prior violent criminal record,” (3) “the Defendant’s record
while incarcerated,” (4) that Lambright “is amenable to some
type of treatment,” (5) the fact that his “military record is a
good one,” and (6) that “[t]here is no record indicating he was
a ‘juvenile delinquent.’ ” None of these potentially mitigating
circumstances was described with any particularity, nor did
Brogna point to any evidence in the record to support the
assertions made in his memorandum.

   In addition to the scant mitigating evidence alluded to by
Brogna, the sentencing judge considered the pre-sentence
report prepared by the probation officer assigned to the case,
a report written by Dr. Richard Hinton — a clinical psycholo-
gist with the Pima County Court’s clinic — and the testimony
of the prosecution’s sole penalty phase witness, who was the
lead detective on the case, and who testified about the circum-
stances under which the victim was raped and murdered.

   Dr. Hinton’s report was based on a psychological evalua-
tion of Lambright, which he performed shortly after Lam-
bright’s conviction. Brogna did not provide Dr. Hinton with
any information regarding Lambright’s childhood, his service
in the military, his history of mental health problems, his
medical history, or his long-term drug abuse, either prior to
the time that Dr. Hinton conducted his evaluation or prior to
the time that he prepared his report. As a result, Dr. Hinton
relied exclusively on his interview with Lambright and on
police reports, newspaper articles, and other materials related
to the offense.

  Dr. Hinton’s report, which presented a very negative and
damning picture of Lambright, contained some basic informa-
                     LAMBRIGHT v. SCHRIRO                    7737
tion about potentially mitigating aspects of Lambright’s back-
ground, including the fact that Lambright had moved
frequently as a child, that he had served in the Air Force in
Vietnam during which time he had allegedly engaged in hand-
to-hand combat, that he had once suffered a nervous break-
down which necessitated his admission to the psychiatric unit
at a Veterans Administration hospital in Houston, Texas, that
he attempted suicide on two occasions, and that he had a long
history of drug abuse. Based on his interview with Lambright,
Dr. Hinton diagnosed him with antisocial personality disorder
and included this diagnosis in his report.

   The pre-sentence report, like Dr. Hinton’s report, contained
some potentially mitigating information regarding Lam-
bright’s personal history but was overwhelmingly more
aggravating than mitigating. It contained a detailed descrip-
tion of the offense, a summary of a telephone conversation
between the victim’s mother and the probation officer who
prepared the report, in which the victim’s mother stated that
both defendants should receive the death penalty. It also con-
tained a summary of the defendant’s social history, emphasiz-
ing his negative personality traits and behavior. The pre-
sentence report did note, however, that “[t]he defendant has
no official, verifiable record of juvenile offenses,” that Lam-
bright had been raised by “a very strict, hypochondriacal,
Pentecostal mother,” and that “[a]t the age of nine or ten, he
began running away from home.”

   Regarding Lambright’s history of mental health problems,
the pre-sentence report contained the following information:

    [T]he defendant described how he had a breakdown
    after his return from Viet Nam, apparently experi-
    encing generalized feelings of paranoia in conjunc-
    tion with feelings of failure over his first marriage.
    His sister described how they found him cowering
    on their front porch one evening, holding a butcher
    knife to protect himself from imagined attackers.
7738                   LAMBRIGHT v. SCHRIRO
       After spending three days in a Houston veterans
       administration hospital, he left against medical
       advice. Attending physicians apparently told his sis-
       ter that if the defendant did not receive long-term
       therapy, he would probably spend the rest of his life
       running from place to place . . .

  As for Lambright’s history of drug use, the pre-sentence
report noted that “[t]he defendant has used and abused various
substances over the past ten years, most notably marijuana,
amphetamines, and alcohol. . . . He has never received any
type of treatment for substance abuse.”

   Brogna’s argument at the close of the sentencing proceed-
ing, like his presentation of mitigating evidence, was
extremely brief. He asked the court to consider the fact that
Kathy Foreman, although a direct participant in the crime,
received no punishment, stated that Dr. Hinton’s conclusion
that Lambright suffers from antisocial personality disorder
was unfounded, and asked the court to consider Lambright’s
lack of a violent history. He did not ask for leniency, but
instead, without any explanation of his reasons, merely
requested that the court impose a sentence of life in prison.

III.    The Death Verdict and State Appeals

   After the very brief sentencing proceeding, the sentencing
judge found that only one aggravating circumstance existed,
namely “that the offense was committed in an especially hei-
nous, cruel or depraved manner.” He nonetheless sentenced
Lambright to death because he found that the limited mitigat-
ing evidence presented was insufficiently substantial to out-
weigh this single aggravating factor. The judge noted that
under Arizona law, “ ‘[t]he Court . . . shall impose a sentence
of death if it finds one or more aggravating circumstances and
finds no mitigating circumstances sufficiently substantial to
call for leniency.’ ” In light of his finding that the mitigating
evidence presented was insubstantial, he concluded that “the
                      LAMBRIGHT v. SCHRIRO                    7739
law demands the maximum penalty . . .” The sentencing judge
did not list Lambright’s long history of substance dependency
or his mental heath problems among the mitigating factors he
considered. With respect to Lambright’s childhood, he said
only that Lambright’s “unsettled early life” was not signifi-
cantly mitigating. Lambright’s conviction and death sentence
were affirmed by the Arizona Supreme Court both on direct
appeal and in subsequent state habeas proceedings. State v.
Lambright, 673 P.2d 1 (Ariz. 1983). Thereafter, in April of
1987, Lambright petitioned for federal habeas corpus relief on
various grounds.

IV.   Federal Habeas Review

   In July of 1996, the district court denied Lambright’s
habeas petition, and Lambright appealed. In January of 1999,
we issued an opinion reversing his conviction on the ground
that the “single trial before ‘dual juries’ ” violated his right to
due process under the Fourteenth Amendment. Lambright v.
Stewart, 167 F.3d 477, 479 (Lambright I), withdrawn, 177
F.3d 901 (9th Cir. 1999). The court later reheard the case en
banc, reversed the panel’s decision, and affirmed the district
court’s denial of relief with respect to the dual jury issue.
Lambright v. Stewart, 191 F.3d 1181, 1182, 1187 (9th Cir.
1999) (en banc) (Lambright II). The case was then returned
to this panel for resolution of Lambright’s remaining claims.
Id. at 1187. We affirmed the district court’s denial of his
habeas petition with respect to all of his guilt phase claims
and all but one of his penalty phase claims, but reversed the
district court’s ruling that his penalty phase ineffective assis-
tance of counsel claim had been procedurally defaulted. Lam-
bright v. Stewart, 241 F.3d 1201, 1203 (9th Cir. 2001)
(Lambright III); Lambright v. Stewart, 5 Fed. Appx. 712, 713-
15 (9th Cir. 2001). After finding that Lambright “presented
more than enough evidence to establish a colorable claim for
deficient performance[,]” we remanded the case to the district
court for an evidentiary hearing on the issue of “whether
Lambright was denied effective assistance of counsel at sen-
7740                 LAMBRIGHT v. SCHRIRO
tencing because of the failure to investigate and present evi-
dence of his psychiatric condition and social history.”
Lambright III, 241 F.3d at 1208.

V.     The Evidentiary Hearing

   In November of 2003, the district court held a six-day evi-
dentiary hearing on the issue of ineffective assistance of coun-
sel. The testimony, affidavits, and other evidence introduced
at the evidentiary hearing revealed that there was a substantial
amount of mitigating evidence that Brogna could have inves-
tigated, developed, and presented at Lambright’s sentencing
hearing. With respect to Lambright’s childhood, the evidence
presented at the evidentiary hearing revealed that Lambright’s
mother beat him severely and regularly from the time he was
a small child until he was fourteen years old, usually by whip-
ping him with various objects, kicking him, or striking him.

   Testimony at the hearing also revealed that Lambright’s
mother presented symptoms of severe hypochondria, and was
profoundly addicted to prescription drugs throughout Lam-
bright’s childhood. She took sleeping pills, Valium, and Dar-
von on a daily basis and, as a result, spent most of her time
in bed, leaving Lambright to fend for himself. Starting around
the time that he was nine years old, she often forced him to
take sedatives in order to make him settle down or sleep. She
was also extremely verbally and emotionally abusive toward
Lambright throughout his childhood. Lambright’s father
ignored his wife’s abusive behavior and did nothing to stop it.

   Evidence was also presented regarding the poverty that
Lambright experienced as a child. According to Lambright’s
sister, the family was “very poor” throughout their childhood.
They often lived in homes with no running water or indoor
plumbing. Once, they were forced to move into a rat-infested
house in which the walls and ceilings were lined with card-
board to block holes. Moreover, throughout Lambright’s
childhood, his family moved every six to nine months because
                     LAMBRIGHT v. SCHRIRO                 7741
his father had difficulty maintaining steady employment. As
a result, Lambright never attended the same school for more
than a year, had difficultly forming relationships with class-
mates, and was a frequent target of bullies. He stopped attend-
ing school altogether after the ninth grade.

   Evidence related to Lambright’s mental heath problems and
long history of drug abuse was also presented. Lambright’s
first wife testified that, prior to 1968 when Lambright was
deployed to Vietnam, he was a kind, gentle, and loving person
who neither drank nor did drugs. When he returned from
Vietnam, he seemed deeply traumatized and his personality
had radically changed. He had trouble maintaining stable,
healthy relationships, was constantly jumpy and agitated, had
difficulty sleeping, was plagued by nightmares, and became
deeply depressed. He would often lock himself in another
room and would say that he wished he were dead. He eventu-
ally became so despondent that he attempted suicide by driv-
ing his car into a tree.

  On one occasion, Lambright’s sister awoke to find him
pounding on her door at two o’clock in the morning. When
she came to the door, she saw Lambright cowering against a
wall, swinging a butcher knife. He was hallucinating and
appeared to be hiding from an imagined attacker. He kept say-
ing “I gotta get to ‘em. I see ‘em. They’re burning Mama and
Daddy, they’re burning.” During this incident Lambright was
crying, incoherent, and “shaking all over.”

  Thereafter, Lambright was admitted to the mental health
unit of the Houston VA hospital. After three days of treat-
ment, Lambright left the hospital against the advice of his
doctors because he was concerned about losing his job and
not being able to support his wife and young son.

   In 1970, Lambright began working as a truck driver and
started using speed and diet pills to stay awake for long peri-
ods of time. In 1971, after his father’s death, he became pro-
7742                  LAMBRIGHT v. SCHRIRO
foundly depressed and began drinking heavily and regularly.
In 1972, Lambright began using marijuana and experimenting
with various other drugs, including acid, hash, cocaine, and
mushrooms. In 1974, Lambright attempted suicide for a sec-
ond time, this time by intentionally overdosing on drugs, and
was briefly hospitalized as a result. Lambright began using
crystal methamphetamine (“meth”) in 1976 or 1977, and by
1979, he would stay high on meth for weeks at a time.

   With respect to his time in Vietnam, Lambright testified
about a traumatic combat experience in which he witnessed
the violent death of a close friend who was shot and killed by
the Vietcong. However, the testimony of other witnesses, as
well as other evidence presented at the evidentiary hearing,
indicated that this event did not occur. Conceivably, it was a
figment of Lambright’s imagination. Also conceivably, it was
a story he concocted.

   Expert testimony was also presented with respect to Lam-
bright’s mental health and substance abuse problems. The
psychiatrist who testified on Lambright’s behalf, Dr. Barry
Morenz, concluded that Lambright’s Vietnam experience,
along with the abuse Lambright experienced at the hands of
his mother, caused Lambright to develop post-traumatic stress
disorder (“PTSD”). The psychologist testifying on behalf of
the state, Dr. Gina Lang, rejected this diagnosis, primarily
because she believed that Lambright’s account of his experi-
ence in Vietnam was fabricated. Both experts agreed, how-
ever, that Lambright suffers from a depressive disorder and
from polysubstance dependency. Dr. Lang also concluded that
Lambright suffers from a personality disorder with antisocial,
borderline, and inadequate features.

  Dr. Hinton, the psychologist who submitted a report to the
sentencing judge in 1982 stating that Lambright suffered from
antisocial personality disorder, also testified at the evidentiary
hearing. He initially stated that if he had been provided by
Brogna with information about Lambright’s background, he
                     LAMBRIGHT v. SCHRIRO                  7743
might have been inclined to infer that Lambright suffered
from PTSD, but upon cross-examination acknowledged that
such a diagnosis would be improbable. He did not deny, how-
ever, that Lambright suffered from some type of mental disor-
der.

VI. The District Court’s Memorandum of Decision and
Order

   On August 30, 2004, the district court issued a memoran-
dum of decision and order denying Lambright’s habeas peti-
tion. The court found that “Petitioner’s testimony with respect
to the trauma underlying his expert’s PTSD diagnosis (the
alleged combat experience) is less than credible.” The court
further found Dr. Morenz’s PTSD diagnosis unpersuasive
because it “rests almost exclusively on the alleged combat
experience as the traumatic trigger event,” and instead found
Dr. Lang’s assessment of Lambright’s mental health problems
to be the more persuasive of the two. Moreover, the court
stated that even if it were “persuaded that Petitioner suffered
from PTSD, Petitioner has failed to show how the disorder
affected his criminal behavior.” The court further found “no
credible evidence that methamphetamine abuse contributed to
Petitioner’s criminal actions” and that “Petitioner . . . pre-
sented no evidence to support the assertion that he was under
the influence of drugs at the time of the crime.”

   Analyzing Lambright’s claim of ineffective assistance of
counsel, the district court concluded that Brogna had provided
adequate representation in spite of the fact that he failed to
present mitigating evidence related to Lambright’s prolonged
drug abuse, mental health problems, and abusive childhood.
With regard to the drug abuse, the court stated that it “cannot
say that it was unreasonable not to focus on drug abuse as a
mitigating factor in the absence of any explanatory nexus to
the crime.” Turning to Brogna’s failure to present evidence
related to Lambright’s history of mental instability and specif-
ically his experiences in Vietnam, the court stated that
7744                 LAMBRIGHT v. SCHRIRO
    [c]ounsel cannot be faulted for failing to investigate
    PTSD when neither Petitioner, his sister nor Dr. Hin-
    ton suggested that the few months Petitioner spent in
    Vietnam so altered him that the experience provided
    a possible explanation for Petitioner’s participation
    in the killing.

The court made no further comment regarding Lambright’s
mental instability or the expert testimony supporting the exis-
tence of a mental disorder other than PTSD. With regard to
Lambright’s abusive childhood, the court concluded that “Pe-
titioner’s upbringing was not so horrific that it significantly
affected Petitioner’s conduct at the time of the crime.”
Accordingly, the court held that “Brogna’s presentation [of
mitigating evidence] was not constitutionally deficient.”

   The court further held that, “[a]ssuming Brogna’s represen-
tation was objectively unreasonable, Petitioner is unable to
establish that Brogna’s errors prejudiced him.” Specifically,
the court concluded that

    [b]ecause Petitioner has failed to establish that he
    was in combat or suffered from PTSD, the Court
    cannot say that Petitioner’s sentence would have
    been different had Brogna conducted a full-blown
    investigation into Petitioner’s Vietnam experiences.
    Moreover, even if PTSD were a viable diagnosis, it
    has not been shown to have any explanatory or
    exculpatory attributes with respect to [the victim’s]
    murder . . .

Regarding Lambright’s substance abuse problem, the district
court concluded that

    the sentencing judge was already well aware of it
    through the presentence report. . . . In addition, Peti-
    tioner never argued that he was under the influence
    of alcohol or drugs when he committed the murder.
                         LAMBRIGHT v. SCHRIRO                        7745
      Therefore, any evidence of substance abuse could
      not have mitigated the circumstances of the crime
      itself.

With respect to Lambright’s childhood, the court concluded
that “Petitioner’s childhood, though bleak, was largely identi-
fied to the sentencing judge. . . . The Court has already noted
that Petitioner failed to prove his upbringing affected his abil-
ity to know right from wrong or to control his conduct.”
Based on these conclusions, the court held that because “the
avenues of potential mitigation evidence are either unsubstan-
tiated or were already before the sentencing judge, the Court
is not persuaded that any deficiencies in counsel’s representa-
tion rendered the sentencing proceeding ‘fundamentally unfair
or unreliable.’ ”

   On appeal, Lambright argues that the district court erred in
(1) holding that Brogna’s investigation and presentation of
mitigating evidence was not constitutionally deficient, and (2)
holding that any deficiency in Brogna’s performance was not
prejudicial. Lambright also argues that the district court com-
mitted two specific errors in reaching these conclusions: (1)
that it erroneously required a causal nexus between his prof-
fered mitigating evidence and the crime, and (2) that it erred
in concluding that Lambright could not assert, during cross-
examination, a Fifth Amendment privilege with regard to
questions related to the offense and likewise erred in drawing
a negative inference regarding certain contested factual issues
based on his refusal to answer such questions.2
  2
    We need not reach Lambright’s argument that the district court erred
in drawing adverse inferences based on his refusal to answer questions
related to the crime as any error in drawing these inferences was harmless.
Neither of the two inferences drawn is of consequence to our analysis of
the ineffective assistance of counsel claim. The first adverse inference —
that Lambright was not on drugs when he committed the offense — is
irrelevant given that Lambright does not argue on appeal that he was in
fact on drugs at that time but only that his history of drug addiction is a
7746                      LAMBRIGHT v. SCHRIRO
                             DISCUSSION

I.    Standard of Review

   Lambright’s federal habeas petition was filed prior to the
enactment of the Antiterrorism and Effective Death Penalty
Act of 1996 (“AEDPA”), and thus, pre-AEDPA standards
apply to his claims. Douglas v. Woodford, 316 F.3d 1079,
1085 (9th Cir. 2003). We review the district court’s decision
to deny habeas relief de novo. Raley v. Ylst, 470 F.3d 792, 799
(9th Cir. 2006). “Under pre-AEDPA law, we consider a claim
alleging ineffective assistance of counsel as a mixed question
of law and fact that we review de novo.” Summerlin v. Schiro,
427 F.3d 623, 628 (9th Cir. 2005) (en banc) (citing Rios v.
Rocha, 229 F.3d 796, 799 n.4 (9th Cir. 2002)). “We review
for clear error, however, the district court’s findings of fact.”
Frierson v. Woodford, 463 F.3d 982, 988 (9th Cir. 2006).
Finally, “[b]ecause this is a pre-AEDPA case, we do not
review the state court’s legal conclusions to determine
whether they are ‘objectively unreasonable;’ rather, we ‘sim-
ply resolve the legal issue on the merits, under the ordinary
rules.’ ” Summerlin, 427 F.3d at 628 (quoting Belmontes v.
Brown, 414 F.3d 1094, 1101 (9th Cir. 2005), rev’d on other
grounds, Ayers v. Belmontes, ___ U.S. ___, 127 S.Ct. 469
(2006)).

II.    The District Court’s Erroneous Application of a
       Nexus Requirement

   [1] At the outset, we reject the district court’s analysis with
respect to deficient performance and prejudice because it is

mitigating factor in and of itself. The second inference — that Lambright’s
alleged Vietnam experience did not affect his behavior at the time of the
offense — is likewise irrelevant given that we hold, for purposes of this
appeal, that the district court did not clearly err in finding that the alleg-
edly traumatic experience never occurred.
                     LAMBRIGHT v. SCHRIRO                     7747
predicated on the application of a legal test that is clearly
inapplicable. The district court disregarded virtually all of the
mitigating evidence that Lambright presented at the evidenti-
ary hearing on the basis that it had no “explanatory nexus” to
the crime. In so doing, it misapplied controlling Supreme
Court and Ninth Circuit precedent. In Tennard v. Dretke, 542
U.S. 274 (2004), the Supreme Court explicitly rejected the
Fifth Circuit’s requirement that mitigating evidence have
some nexus or causal connection to the crime of which the
capital defendant was convicted in order for a jury’s failure to
consider that evidence to be deemed prejudicial. Id. at 289.
The Court held that

    [t]he Fifth Circuit’s test has no foundation in the
    decisions of this Court. . . . When we [have]
    addressed directly the relevance standard applicable
    to mitigating evidence in capital cases . . . we [have]
    spoke[n] in the most expansive terms. . . . The Fifth
    Circuit’s test is inconsistent with these principles.
    Most obviously, the test will screen out any positive
    aspect of a defendant’s character because good char-
    acter traits are . . . no[t] typically traits to which
    criminal activity is “attributable.”

Id. at 284-85. Turning specifically to the “nexus” element of
the Fifth Circuit’s test, the Court held that

    [t]he Fifth Circuit was . . . wrong to have refused to
    consider . . . [Tennard’s claim] on the ground that
    Tennard had not adduced evidence that his crime
    was attributable to his low IQ. In Atkins v. Virginia,
    536 U.S. 536 304, 316 (2002), we explained that
    impaired intellectual functioning is inherently miti-
    gating . . . Nothing in our opinion suggested that a
    mentally retarded individual must establish a nexus
    between her mental capacity and her crime before
    the Eighth Amendment prohibition on executing her
    is triggered. Equally, we cannot countenance the
7748                 LAMBRIGHT v. SCHRIRO
    suggestion that low IQ evidence is not relevant miti-
    gating evidence . . . unless the defendant also estab-
    lishes a nexus to the crime.

Id. at 287.

   In Smith v. Texas, 543 U.S. 37, 45 (2004), the Court reiter-
ated that it had “rejected the . . . ‘nexus’ requirement in Ten-
nard,” and stated that “petitioner’s evidence [regarding his
troubled childhood and limited mental abilities] was relevant
for mitigation purposes is plain under our precedents.” Id.
(citing Penry v. Lynaugh, 492 U.S. 302, 319-20 (1989); Payne
v. Tennessee, 501 U.S. 808, 822 (1991); Boyde v. California,
494 U.S. 370, 377-78 (1990); Eddings v. Oklahoma, 455 U.S.
104, 114 (1982)). Indeed, the Court has characterized the
“nexus” test as “a test we never countenanced and now have
unequivocally rejected.” Id.

   [2] We, too, have addressed the question whether evidence
with no explanatory nexus to the crime at issue should be con-
sidered mitigating in Smith v. Stewart, 140 F.3d 1263, 1271
(9th Cir. 1998), and we did so in the context of assessing
whether counsel’s deficient performance in a capital sentenc-
ing proceeding was prejudicial. Id. We held specifically that
the issue of whether counsel’s failure to present evidence
related to antisocial personality disorder and long-term drug
use was prejudicial did not turn on “whether those precluded
[the defendant] from knowing right from wrong, as the
postsentencing court and the district court seemed to have
assumed” and as they would have to have done for there to
be a nexus between those factors and the crime. Id. Instead,
we held that “they need not do so in order to be . . . mitiga-
tors.” Id.

   The reason for rejecting a nexus requirement is clear: “ ‘the
fundamental respect for humanity underlying the Eighth
Amendment . . . requires consideration of the character and
record of the individual offender . . . as a constitutionally
                      LAMBRIGHT v. SCHRIRO                   7749
indispensable part of the process of inflicting the penalty of
death.’ ” Eddings, 455 U.S. at 112 (quoting Woodson v. North
Carolina, 428 U.S. 280, 304 (1976)). If evidence relating to
life circumstances with no causal relationship to the crime
were to be eliminated, significant aspects of a defendant’s dis-
advantaged background, emotional and mental problems, and
adverse history, as well as his positive character traits, would
not be considered, even though some of these factors, both
positive and negative, might cause a sentencer to determine
that a life sentence, rather than death at the hands of the state,
is the appropriate punishment for the particular defendant.
This is simply unacceptable in any capital sentencing pro-
ceeding, given that “treating each defendant in a capital case
with that degree of respect due the uniqueness of the individu-
al,” and determining whether or not he is deserving of execu-
tion only after taking his unique life circumstances,
disabilities, and traits into account, is constitutionally
required. Lockett v. Ohio, 438 U.S. 586, 605 (1978).

   [3] Here, the district court relied heavily on its finding that
Lambright had not shown a nexus between his proffered miti-
gating evidence and the crime, flatly rejecting the majority of
the mitigating evidence he offered on that basis. Indeed, it is
apparent from the district court’s order that it either did not
consider mitigating any evidence without an explicit nexus to
the crime, or that it gave such evidence de minimus weight.
Because the district court’s rejection of Lambright’s mitigat-
ing evidence on that basis violates the rule set forth in Ten-
nard, Smith v. Texas, Smith v. Stewart, and their predecessors,
we hold that its analysis of Lambright’s ineffective assistance
of counsel claim was fundamentally flawed.

III.   Ineffective Assistance of Counsel

   We begin by assessing whether Brogna’s performance at
sentencing was so deficient as to violate Lambright’s right to
counsel under the Sixth Amendment. “The Sixth Amendment
right to counsel in a criminal trial includes ‘the right to the
7750                  LAMBRIGHT v. SCHRIRO
effective assistance of counsel.’ ” Summerlin, 427 F.3d at 629
(quoting McMann v. Richardson, 397 U.S. 759, 771 n.14
(1970)). “This right extends to ‘all critical stages of the crimi-
nal process,’ including capital sentencing.” Id. (citations omit-
ted).

   In order to prevail on a claim of ineffective assistance of
counsel, a petitioner must show that (1) his trial counsel’s per-
formance “fell below an objective standard of reasonable-
ness”; and (2) “there is a reasonable probability that, but for
counsel’s unprofessional errors, the result of the proceeding
would have been different.” Strickland v. Washington, 466
U.S. 668, 687-88, 694 (1984).

  A.   Deficient Performance

   Under Strickland, counsel’s competence is presumed and
thus Lambright must rebut this presumption by demonstrating
that Brogna’s performance was unreasonable under prevailing
professional norms and was not the product of sound strategy.
See id. at 688-89. Judicial scrutiny of counsel’s performance
is highly deferential, and thus we must evaluate Brogna’s con-
duct from his perspective at the time it occurred, without the
benefit of hindsight. Id. at 689. “[S]trategic choices made
after thorough investigation of [the relevant] law and facts rel-
evant to plausible options are virtually unchallengeable.” Id.
at 690. However,

    strategic choices made after less than complete
    investigation are reasonable precisely to the extent
    that reasonable professional judgments support the
    limitations on investigation. In other words, counsel
    has a duty to make reasonable investigations or to
    make a reasonable decision that makes particular
    investigations unnecessary. In any ineffectiveness
    case, a particular decision not to investigate must be
    directly assessed for reasonableness in all the cir-
    cumstances . . .
                      LAMBRIGHT v. SCHRIRO                   7751
Id. at 690-91; see also Wiggins v. Smith, 539 U.S. 510, 521
(2003) (quoting Strickland, 466 U.S. 690-91). Similarly, a
decision not to present a particular defense or not to offer par-
ticular mitigating evidence is unreasonable unless counsel has
explored the issue sufficiently to discover the facts that might
be relevant to his making an informed decision. Wiggins, 539
U.S. at 522-23; Stankewitz v. Woodford, 365 F.3d 706, 719
(9th Cir. 2004).

   The Supreme Court has “declined to articulate specific
guidelines for appropriate attorney conduct and instead ha[s]
emphasized that ‘the proper measure of attorney performance
remains simply reasonableness under prevailing professional
norms.’ ” Wiggins, 539 U.S. at 521 (quoting Strickland, 466
U.S. at 688). “However, general principles have emerged
regarding the duties of criminal defense attorneys that inform
our view as to the ‘objective standard of reasonableness’ by
which we assess attorney performance, particularly with
respect to the duty to investigate.” Summerlin, 427 F.3d at
629.

   [4] For example, we have held that “ ‘[t]o perform effec-
tively . . . counsel must conduct sufficient investigation and
engage in sufficient preparation to be able to ‘present[ ] and
explain[ ] the significance of all the available [mitigating] evi-
dence.’ ” Allen v. Woodford, 395 F.3d 979, 1000 (9th Cir.
2005) (citing Mayfield v. Woodford, 270 F.3d 915, 927 (9th
Cir. 2001) (en banc)); see also Summerlin, 427 F.3d at 630.
Indeed, we have consistently held that “ ‘it is imperative that
all relevant mitigating information be unearthed for consider-
ation at the capital sentencing phase.’ ” Wallace v. Stewart,
184 F.3d 1112, 1117 (9th Cir. 1999) (quoting Caro v. Calde-
ron, 165 F.3d 1223, 1227 (9th Cir. 1999)).

  “To that end, the investigation should include inquiries into
social background and evidence of family abuse.” Summerlin,
427 F.3d at 630. Attorneys representing defendants in capital
sentencing proceedings also have a “ ‘duty to investigate and
7752                 LAMBRIGHT v. SCHRIRO
present mitigating evidence of mental impairment’ . . . [,]
[which] includes examination of mental health records.” Id.
(quoting Bean v. Calderon, 163 F.3d 1073, 1080 (9th Cir.
1998) and citing Deutscher v. Whitley, 884 F.2d 1152, 1161
(9th Cir. 1989)); see also Caro v. Woodford, 280 F.3d 1247,
1254 (9th Cir. 2002). Furthermore, “counsel has an affirma-
tive duty to provide mental health experts with information
needed to develop an accurate profile of the defendant’s men-
tal health.” Caro v. Woodford, 280 F.3d at 1254. “The defen-
dant’s history of drug and alcohol abuse should also be
investigated.” Summerlin, 427 F.3d at 630 (citing Jennings v.
Woodford, 290 F.3d 1006, 1016-17 (9th Cir. 2002)). Lam-
bright’s counsel did almost none of this in the present case.

   Moreover, when “tantalizing indications in the record” sug-
gest that certain mitigating evidence may be available, those
leads must be pursued. Stankewitz, 365 F.3d at 719-20; see
also Summerlin, 427 F.3d at 632 (finding ineffective assis-
tance where trial counsel failed to obtain readily available evi-
dence concerning possible mental health mitigation where his
client’s prior attorney told him there were indications that the
defendant was mentally ill); Wallace, 184 F.3d at 1115-16
(finding ineffective assistance where trial counsel spent only
two hours interviewing potential witnesses, just over thirty
minutes with a psychiatric expert, and failed to contact known
and willing witnesses); Seidel v. Merkle, 146 F.3d 750, 756
(9th Cir. 1998) (finding ineffective assistance where defense
counsel “failed to conduct even a minimal investigation in
order to make an informed decision” regarding his client’s
mental health defense).

   In Correll v. Ryan, 465 F.3d 1006 (9th Cir. 2006), for
example, we held that petitioner’s trial counsel had been inef-
fective in failing to adequately investigate and present evi-
dence related to the defendant’s background, mental health
problems, and long-term drug addiction at the penalty phase
of his capital trial. Id. at 1012-15. We noted that Correll’s
                     LAMBRIGHT v. SCHRIRO                      7753
    attorney knew that, among other things, Correll
    came from a dysfunctional family, sustained a seri-
    ous head injury, was committed to various psychiat-
    ric facilities, and that he was addicted to drugs; yet
    defense counsel did not obtain the records nor did he
    interview witnesses concerning these matters. Coun-
    sel did meet with the family members who would
    cooperate, but he admitted that he met only once
    with Correll’s father, sister, and brother . . . and
    probably spent “[a] couple hours” with them. Coun-
    sel did not obtain Correll’s school records . . . [He]
    did not obtain Correll’s medical records. . . . [He]
    could not recall what efforts he made to gather Cor-
    rell’s psychiatric records, although defense counsel
    did remember that he did not obtain records from
    Correll’s stays at various mental health centers.

Id. at 1011. Assessing counsel’s mitigation investigation
under the standards set forth above, we concluded that

    in light of the abundance of classic mitigation evi-
    dence of which counsel was aware, his almost com-
    plete failure to investigate is startling. . . . Defense
    counsel’s failure to investigate falls far short of any
    objectively reasonable standard against which we
    might measure attorney performance under the stan-
    dards of the Sixth Amendment.

Id. at 1011-12. Turning to counsel’s presentation of evidence
at the penalty phase, we observed that “[a]s anemic as the
defense counsel’s investigation was, his presentation of miti-
gating evidence . . . was [even] worse.” Id. at 1012. Defense
counsel “did not call a single witness to testify. He did not
introduce any evidence. Rather, he elected to allow the judge
to make a decision on whether to sentence Correll to death
based solely on the state’s evidence and the pre-sentence
report.” Id. Moreover, “[d]efense counsel’s entire mitigation
argument was contained in less than one page of a sentencing
7754                  LAMBRIGHT v. SCHRIRO
memorandum[,] . . . [and t]he entirety of his oral argument at
the penalty phase consist[ed] of approximately 7 pages of
transcript.” Id. at 1013.

   [5] The facts of the case at hand and those in Correll are
strikingly similar. Here, as in Correll, Brogna failed to do
even a minimal investigation of “classic mitigation evidence,”
notwithstanding the fact that he knew such evidence poten-
tially existed. Specifically, although prior to the imposition of
the capital sentence Brogna became aware of Lambright’s his-
tory of mental health problems, the fact that he had attempted
suicide on two prior occasions, and that he had been hospital-
ized in a psychiatric facility as a result, Brogna did not discuss
these issues with Lambright’s friends or family members, nor
did he request Lambright’s medical or hospital records.
Although he knew that Lambright had discussed traumatic
experiences in Vietnam with the probation officer assigned to
prepare the pre-sentence report and with the Pima County
Court’s psychologist, he did not attempt to obtain any infor-
mation about these experiences or their effect on him. Even
after the court’s psychologist prepared a report in which he
concluded that Lambright suffered from antisocial personality
disorder, Brogna did not contact the psychologist to discuss
this diagnosis, nor did he attempt to have another psychologist
or psychiatrist evaluate Lambright. He likewise failed to hire
an independent investigator, despite his awareness that the
court would pay for these additional expenses.

   [6] Brogna also knew that Lambright had a serious drug
problem, but he conducted no investigation with regard to the
extent of his drug use or its effect on his general mental state
or behavior. He likewise did not seek to obtain Lambright’s
school or military records. Nor did he contact either of Lam-
bright’s former wives. Although Brogna traveled with counsel
for Lambright’s co-defendant to Texas and Louisiana for five
days and spoke with a number of potential witnesses prior to
the guilt phase of Lambright’s trial, the trip did not yield any
useful mitigating evidence, and Brogna did no additional
                          LAMBRIGHT v. SCHRIRO                          7755
investigating thereafter. Moreover, it is unclear whether any
of the individuals he spoke with during this trip were people
he viewed as potential penalty phase witnesses. When Brogna
spoke to Lambright’s sister, he primarily asked her about
Lambright’s conduct around the time of the crime and does
not appear to have asked her about Lambright’s upbringing,
his mental health, or other potential mitigating evidence.3
Accordingly, as in Correll, Brogna’s investigation of poten-
tially mitigating evidence was utterly deficient under the stan-
dards established by this court and by the Supreme Court.

   In light of his woefully inadequate investigation, it is not
surprising that Brogna’s presentation at the sentencing pro-
ceeding was minimal and markedly uncompelling. He spent
only five and a half hours obtaining evidence and preparing
for the penalty phase. The sum total of the mitigating evi-
dence that Brogna offered at sentencing required less than
three pages of a double-spaced transcript and relates only to
Lambright’s behavior in jail. Although there were signs at the
time that Lambright suffered from mental illness, his counsel
failed to present any mitigating psychiatric testimony. Instead,
in contravention of his obligation to his client, he relied solely
  3
    At one point in its order, the district court concludes that “Brogna
interviewed Petitioner’s only sibling extensively[.]” The record does not
support the court’s finding that the interview was “extensive.” Brogna tes-
tified that his recollection of his sole interview with Lambright’s sister
was “very vague[ ],” that the interview focused on Lambright’s life shortly
before and after the crime, and that he doesn’t recall whether he talked
with her about Lambright’s upbringing, social history, or mental health
problems. Lambright’s sister’s testimony about this interview is inconsis-
tent, most likely due to the fact that she suffers from memory problems
as the result of a stroke. Thus, we cannot accept the district court’s finding
that this interview was “extensive.” In any event, this finding does not
affect our decision. Even if counsel had spoken to Lambright’s sister about
his childhood, history of drug abuse, and mental health problems prior to
the guilt phase of Lambright’s trial, his total failure to do any other inves-
tigating or to follow up on what he might have learned from her, as well
as his failure to present evidence of any of these mitigating circumstances
to the sentencing judge, would render his assistance ineffective.
7756                 LAMBRIGHT v. SCHRIRO
on the probation officer’s report and that of the court-
appointed psychologist to present any mitigating evidence
regarding Lambright’s mental condition, history of drug
dependency, and disadvantaged childhood. Cf. Correll, 465
F.3d at 1012. Brogna failed to call any of Lambright’s family
members or friends to testify about his abusive childhood, his
history of mental instability, his suicide attempts, or his drug
use. Nor was any testimony offered to humanize Lambright,
or to situate the crime within Lambright’s troubled history.
Instead, Brogna promised the court that he had “one witness
who will be very brief.” This sole witness, a guard at the Pima
County Jail, testified that while Lambright was incarcerated
the guard had experienced no “problems with him” and that
Lambright had “been respectful, courteous, and cooperative.”
Aside from this brief testimony, no mitigating evidence was
introduced by Brogna. Instead, he submitted a two-and-a-half-
page memorandum listing various potentially mitigating cir-
cumstances, including (1) the fact that a deal was cut with
Lambright’s accomplice, Kathy Foreman, (2) Lambright’s
“lack of a prior violent criminal record,” (3) “the Defendant’s
record while incarcerated,” (4) that Lambright “is amenable to
some type of treatment,” (5) the fact that his “military record
is a good one,” and (6) that “[t]here is no record indicating he
was a ‘juvenile delinquent.’ ” However, none of the poten-
tially mitigating circumstances discussed in the memorandum
was described in any detail, nor did Brogna point to any evi-
dence in the record or provide any factual support for his
assertions. Cf. Correll, 465 F.3d at 1013 (noting that no evi-
dence was offered to support the assertions made in trial
counsel’s brief sentencing memorandum).

   Counsel’s argument at the close of the sentencing proceed-
ing was similarly brief and uncompelling. Brogna merely
asked the court to consider the fact that Kathy Foreman, a
willing participant in the crime, received no punishment, that
“[t]here isn’t anything in Mr. Lambright’s background that
establishes the fact that he is a sociopathic personality,” and
that Lambright did not have a violent history. He did not even
                      LAMBRIGHT v. SCHRIRO                     7757
mention Lambright’s unfortunate childhood, his history of
substance abuse, or the mental problems that led him to two
suicide attempts, a bizarre episode in which he wielded a
butcher knife outside his sister’s door, as well as psychiatric
hospitalization. Brogna did not ask for leniency or mercy;
instead, he merely requested, without any elucidation, that the
court impose a sentence of life in prison. Accordingly,
Brogna’s presentation at the penalty phase of Lambright’s
trial, like his mitigation investigation, fell far below the level
of representation to which Lambright was entitled under the
Sixth Amendment. Cf. Correll, 465 F.3d at 1013; Stankewitz,
365 F.3d at 716-17 (finding ineffective assistance where
counsel offered the very general and uncompelling testimony
of six witnesses, and merely summarized briefly petitioner’s
life history “focus[ing] little on the actual details of [his] life”
during closing argument).

   The state argues, and the district court held, that Brogna’s
performance was not deficient because his brief memoran-
dum, along with the pre-sentence report and the report of the
court’s mental health expert, Dr. Hinton, informed the sen-
tencing judge that Lambright experienced a “bleak” child-
hood, that he had a history of drug abuse, and that he
experienced mental health problems. Specifically, the district
court held that Brogna did not perform deficiently because he

    referenced, albeit in abbreviated form, many of the
    same mitigating factors identified in these proceed-
    ings . . . Other factors [not mentioned by Brogna,]
    such as [cursory references to] the suicide attempts,
    hospitalization and abuse of drugs[,] were already
    before the sentencing judge and were considered in
    the weighing process. The Court therefore concludes
    that Brogna’s presentation was not constitutionally
    deficient.

  The district court’s holding contravenes long-established
Ninth Circuit law. As this court has often made clear, coun-
7758                  LAMBRIGHT v. SCHRIRO
sel’s duty to investigate all potentially mitigating evidence
related to a defendant’s mental health, family background,
and prior drug use and to provide the sentencing court with
a full presentation of the evidence that might lead the sen-
tencer to spare his client’s life is not discharged merely by
conducting a limited investigation of these issues or by pro-
viding the sentencing court with a cursory or “abbreviated”
presentation of potentially mitigating factors. Stankewitz, 365
F.3d at 716 (“[C]ounsel’s duty to conduct a thorough investi-
gation . . . is not discharged merely by presenting some lim-
ited evidence.”); see also Wiggins, 539 U.S. at 524 (finding
ineffective assistance and prejudice where “counsel aban-
doned their investigation of petitioner’s background after hav-
ing acquired only rudimentary knowledge of his history from
a narrow set of sources”); Correll, 465 F.3d at 1015 n.5 (hold-
ing that although “the bare facts of [petitioners]’s troubled
past were . . . presented to the court, without further investiga-
tion and presentation of contextual evidence and argument,
such facts served only to demonize [petitioner] rather than to
mitigate the appropriateness of imposing the death penalty for
his actions.”); Douglas, 316 F.3d at 1090 (finding ineffective
assistance where trial counsel “introduced some of [the defen-
dant’s] social history, [but] did so in a cursory manner that
was not particularly useful or compelling.”). To the contrary,
“[w]hen it comes to the penalty phase of a capital trial, ‘[i]t
is imperative that all relevant mitigation information be
unearthed for consideration.’ ” Douglas, 316 F.3d at 1088
(quoting Caro v. Calderon, 165 F.3d at 1227). Only after a
thorough investigation can a less than complete presentation
of mitigating evidence ever be deemed reasonable, and only
to the extent that a reasonable strategy supports such a presen-
tation. Wiggins, 539 U.S. at 527-28; Stankewitz, 365 F.3d at
719. Counsel may not rely for the development and presenta-
tion of mitigating evidence on the probation officer and a
court appointed psychologist. See Correll, 465 F.3d at 1012
(finding “critical error” in counsel’s decision to allow the trial
judge to make a sentencing determination based on the state’s
                     LAMBRIGHT v. SCHRIRO                  7759
evidence and the pre-sentence report). The responsibility to
afford effective representation is not delegable to parties who
have no obligation to protect or further the interests of the
defendant.

   [7] In sum, the record makes plain that Brogna’s limited,
cursory, and incomplete presentation of mitigating evidence
did not take place after “ ‘all relevant mitigation information
[was] unearthed for consideration,’ ” Douglas, 316 F.3d at
1088 (quoting Caro v. Calderon, 165 F.3d at 1227). Instead,
Brogna spent only five and a half hours, following Lam-
bright’s conviction, in preparation for the penalty phase
(including three hours talking to the probation officer, prepar-
ing his subpoena for the jail guard, and dictating the memo to
the court). Meanwhile, he ignored “tantalizing indications in
the record . . . that ‘would [have] le[ ]d a reasonable attorney
to investigate further.’ ” Stankewitz, 365 F.3d at 720 (quoting
Wiggins, 539 U.S. at 527). Compounding his failure to inves-
tigate, Brogna then failed to draw the court’s attention to the
scant mitigating evidence that was before the court through
the pre-sentence report and Dr. Hinton’s report, or to argue
that this evidence should be given mitigating weight. Such
representation falls far below that which any reasonably com-
petent attorney would provide in a capital case. Accordingly,
we hold that the district court erred in concluding that
Brogna’s performance at the penalty phase was not deficient.

  B.   Prejudice

   To establish prejudice, Lambright must demonstrate that
there is “a reasonable probability that, but for counsel’s
unprofessional errors, the result of the proceeding would have
been different.” Strickland, 466 U.S. at 694. A reasonable
probability is one “ ‘sufficient to undermine confidence in the
outcome,’ ” but is “less than the preponderance more-likely-
than-not standard.” Summerlin, 427 F.3d at 640, 643 (quoting
and citing Strickland, 466 U.S. at 693-94). Accordingly, “[i]n
establishing prejudice under Strickland, it is not necessary for
7760                 LAMBRIGHT v. SCHRIRO
the habeas petitioner to demonstrate that the newly presented
mitigation evidence would necessarily overcome the aggra-
vating circumstances.” Correll, 465 F.3d at 1018 (citing Wil-
liams v. Taylor, 529 U.S. 362, 398 (2000)); see also Rompilla
v. Beard, 545 U.S. 374, 393 (2005) (“[A]lthough we suppose
it is possible that [the sentencer] could have heard it all and
still decided on the death penalty, that is not the test.”).
Instead, in evaluating prejudice, we must “compare the evi-
dence that actually was presented to the [sentencer] with the
evidence that might have been presented had counsel acted
differently,” Bonin v. Calderon, 59 F.3d 815, 834 (9th Cir.
1995), and evaluate whether the difference between what was
presented and what could have been presented is sufficient to
“undermine confidence in the outcome” of the proceeding,
Strickland, 466 U.S. at 694.

   [8] Applying these standards, both this court and the
Supreme Court have consistently held that counsel’s failure to
present readily available evidence of childhood abuse, mental
illness, and drug addiction is sufficient to undermine confi-
dence in the result of a sentencing proceeding, and thereby to
render counsel’s performance prejudicial. See, e.g., Rompilla,
545 U.S. at 390-91; Ainsworth v. Woodford, 268 F.3d 868,
878 (9th Cir. 2001); Smith v. Stewart, 140 F.3d at 1271.

   In Smith v. Stewart, we held that prejudice had been estab-
lished where defense counsel did very little investigating,
presented no mitigating evidence, and made only “a few
asthenic comments” on his client’s behalf in spite of the fact
that additional mitigating evidence “was rather near the sur-
face.” Smith v. Stewart, 140 F.3d at 1271. Smith was con-
victed of shooting a convenience store clerk while in the
process of robbing the store, and the state sought the death
penalty. Id. at 1267-68. In preparation for sentencing, Smith’s
counsel spoke with Smith and Smith’s mother. Id. at 1269. He
asked them “about [Smith’s] growing up years, but did not
discover any difficulties worth mentioning, and does not
recall having been made aware of any treatment Smith might
                     LAMBRIGHT v. SCHRIRO                   7761
have received at a medical facility,” most likely because he
“asked nothing more than a few generalized questions and
conducted none of the real probing for information that legal
praxis assumes and even demands.” Id. In light of the evi-
dence Smith presented in support of his habeas petition, we
noted that “counsel could have, at least, pointed to Smith’s
sociopathic personality, his bad drug history, his change in
personality after a large drug overdose, and his fine set of
family relationships at the time” as evidence in mitigation. Id.

   In assessing prejudice, the court noted that the fact that
Smith had a sociopathic personality is mitigating, given that
“[t]he Arizona Supreme Court has made it clear that an anti-
social personality disorder (sociopathic disorder) is a mitigat-
ing factor, even if it does not come up to the level of a factor
specifically listed in the Arizona sentencing statute.” Id. at
1270 (citing State v. Thornton, 929 P.2d 676, 685-86 (Ariz.
1996) and State v. Stokley, 898 P.2d 454, 470-71, 473 (Ariz.
1995)).

    Similarly, Smith’s long use of drugs is a factor that
    could have had a mitigating effect. . . . Along the
    same line, a major personality change can amount to
    a mitigating factor in Arizona. Smith has presented
    some evidence that a change of that nature came
    over him after he had ingested a large amount of
    PCP in 1980. . . . Finally, Smith points to his good
    family relationships. That was before the sentencing
    judge through the presentence report, but in a very
    mild form. With a little effort it could have been
    developed through evidence or argument, and could
    have put Smith himself in a somewhat different
    light.

Id. at 1271 (citing State v. Gallegos, 870 P.2d 1097, 1113
(Ariz. 1994); State v. Rockwell, 775 P.2d 1069, 1079-80
(Ariz. 1989)). Assessing this evidence, we noted that
7762                 LAMBRIGHT v. SCHRIRO
    these factors, even as now developed, do not demand
    a life sentence rather than a sentence of death. On
    the other hand, while the facts of this case are bad
    enough to disturb even a jaded observer, they do not
    reach the level of those in cases where the aggravat-
    ing facts were so overwhelmingly horrifying that it
    was highly improbable that mitigating factors of any
    ordinary stripe would help. . . . In fine, and with all
    due respect to those who have heard this case before
    us, our confidence in the sentencing result has been
    undermined.

Id. (citations omitted).

   Here, as in Smith, significant mitigating evidence was
available but was never developed or presented to the sen-
tencing judge. Here, too, there was some limited and unsub-
stantiated mitigating evidence before the court through the
pre-sentence report and Dr. Hinton’s report, but counsel failed
to develop it or even argue that the court should consider it.
Indeed, the evidence that could have been presented or relied
upon at Lambright’s sentencing hearing is strikingly similar
to the evidence the absence of which undermined our confi-
dence in the outcome of the sentencing proceeding at issue in
Smith. Specifically, the failure to offer the following evidence
that could and should have been developed and presented was
prejudicial.

    1.   Lambright’s Traumatic Childhood

   [9] The district court found that facts related to Lambright’s
childhood “w[ere] largely identified to the sentencing judge,”
and based on that finding concluded that Brogna’s failure to
develop this evidence was not prejudicial. This finding is
clearly erroneous, that the resulting conclusion lacks support.
While the pre-sentence report and Dr. Hinton’s report did pro-
vide some very limited information about Lambright’s
upbringing, the picture of his childhood presented in the
                      LAMBRIGHT v. SCHRIRO                   7763
reports was inaccurate, undeveloped, and unsubstantiated.
Had Brogna conducted a reasonable investigation, he would
have been able to present compelling evidence showing that
Lambright was subjected to near constant emotional and
physical abuse by his mother throughout his childhood, and
that his father did nothing to stop this abuse. Specifically, tes-
timony could have been offered to show that his mother fre-
quently hit, kicked, or whipped him, and that these beatings
were a daily occurrence during extended periods of his child-
hood. Although the sentencing court may have been aware
that Lambright’s mother was “very strict” and was “ill-
equipped with the necessary parenting skills” to raise two
children, given that these facts were briefly mentioned in the
pre-sentence report, no evidence regarding the significant
physical abuse Lambright experienced as a child was devel-
oped or presented to the sentencing court.

   Similarly, although the pre-sentence report noted that Lam-
bright’s mother was hypochondriacal and strictly Pentecostal,
it did not convey the fact that she spent the majority of Lam-
bright’s childhood in bed claiming to be afflicted by various
illnesses, nor that she was profoundly addicted to prescription
drugs. The sentencing judge was also unaware of the fact that
Lambright’s mother forced him to take Valium and sleeping
pills when he acted up or had too much energy.

   Although the pre-sentence report and Dr. Hinton’s report
noted that Lambright’s family moved frequently during his
childhood, these reports did not effectively convey the extent
to which these moves prevented Lambright from developing
stable social relationships as a young child — relationships
that might have mitigated the effect of his abusive home envi-
ronment. The court was also unaware that Lambright never
attended any school for more than a year and, as a result, had
difficulty forming friendships with other children and was a
frequent target of schoolyard bullies.

   The sentencing judge was likewise unaware of the poverty
that Lambright experienced while growing up. In the pre-
7764                 LAMBRIGHT v. SCHRIRO
sentence report, the probation officer noted that according to
Lambright and his older sister, they were raised in a lower-
middle class family. The sentencing judge did not know that
their constant moves were necessitated by their father’s strug-
gle to maintain steady employment, and that the family once
was forced to move into a rat-infested house in which the
walls and ceilings were lined with cardboard to block holes.
He likewise did not know that they often lived in houses with
no running water or indoor plumbing.

  [10] Accordingly, Lambright has demonstrated that com-
pelling mitigating evidence could and should have been pres-
ented regarding his childhood, evidence that, at least in
combination with the evidence that Brogna failed to present
regarding Lambright’s long-term drug abuse and impaired
mental condition, undermines our confidence in the result.
Such failure was, accordingly, prejudicial.

    2.   Lambright’s Long-Term Drug Use and Dependency

   The district court concluded that “the sentencing judge was
already well aware of [Lambright’s history of drug abuse]
through the pre-sentence report. There was not much more
evidence that Brogna could have uncovered that would have
been helpful or that the sentencing judge did not already know
with respect to [Lambright’s] drug use.” This conclusion is
likewise clearly erroneous in light of the evidence presented
at the evidentiary hearing. Although the pre-sentence report
and Dr. Hinton’s report did mention Lambright’s drug use,
together the reports contained only a few sentences on this
point, and provided incomplete, uncompelling, and uncorrob-
orated information. Neither report contained any information
about the extent to which these drugs affected Lambright’s
development or his social relationships, nor the nature of their
effect on him. Had Brogna properly developed evidence
regarding Lambright’s long history of drug dependency, he
would have been able to show that drug and alcohol abuse
were rampant in Lambright’s family and that, as noted above,
                         LAMBRIGHT v. SCHRIRO                          7765
it was his mother who first exposed him to drug abuse by
forcing him to take sedatives when he was a child. Brogna
could have presented further evidence regarding the fact that
there were periods in Lambright’s life during which he took
large quantities of methamphetamine, staying awake for
weeks at a time. He could have presented evidence about the
negative impact drug abuse had on his ability to form relation-
ships, and could have provided expert testimony about the
long-term psychological impact on him of his extreme
methamphetamine abuse. At the evidentiary hearing, even the
state’s expert, Dr. Lang, diagnosed Lambright with profound
substance dependency.

   [11] Accordingly, significant evidence related to Lam-
bright’s long-term drug addiction and its effect upon him was
available but was not presented to or urged upon the sentenc-
ing court, evidence which, in combination with the evidence
Brogna failed to introduce regarding Lambright’s childhood
and his mental health problems, undermines our confidence in
the result. The failure to present such evidence was, accord-
ingly, prejudicial.

      3.   Lambright’s Mental Health Problems

   The district court found that Lambright’s “testimony with
respect to the trauma underlying his expert’s PTSD diagnosis
(the alleged combat experience) is less than credible.” On the
basis of the testimony and other evidence offered at the evi-
dentiary hearing, we conclude that this finding is not clearly
erroneous.4 However, because it considered only the question
whether Lambright had proved that he suffered from PTSD,
  4
   The district court erred, however, in declaring that even if it were “per-
suaded that the Petitioner suffered from PTSD, Petitioner has failed to
show how the disorder affected his criminal conduct.” As we explained
supra at Part II, there need not be a causal connection between a factor,
such as mental illness, disturbed childhood, or drug dependency, and the
criminal offense in order for it to be mitigating.
7766                 LAMBRIGHT v. SCHRIRO
the district court failed to discuss evidence establishing that
Lambright did suffer from various other mental health prob-
lems. Moreover, irrespective of whether Lambright suffered a
traumatic combat experience in Vietnam, there was testimony
presented at the evidentiary hearing that he was a very differ-
ent person once he returned from his tour of duty. Cf. Smith
v. Stewart, 140 F.3d at 1271 (“[A] major personality change
can amount to a mitigating factor in Arizona.”).

   In addition, testimony at the evidentiary hearing described
Lambright’s lifelong struggle with depression. Dr. Morenz,
Lambright’s mental health expert, testified that Lambright has
experienced varying levels of depression for most of his life,
and at times has suffered from “major depression.” Even Dr.
Lang, the state’s expert, diagnosed him with a depressive dis-
order. As a result of his profound depression, Lambright twice
attempted suicide. Moreover, on at least one occasion, Lam-
bright experienced hallucinations and was hospitalized as a
result.

   Expert testimony presented at the evidentiary hearing also
suggested that Lambright may suffer from a personality disor-
der. Dr. Lang, the state’s expert, whose assessment of Lam-
bright’s mental health problems the district court found
credible, concluded that Lambright suffers from a personality
disorder not otherwise specified with antisocial, borderline,
and inadequate features. This diagnosis, if properly developed
and explained to the sentencer, would have had a mitigating
effect under Arizona law, as noted in Smith v. Stewart, 140
F.3d at 1270 (citing Thornton, 929 P.2d at 685-86; Stokley,
898 P.2d at 470-71, 473).

   [12] While the sentencing court was provided with some
limited information about Lambright’s mental health prob-
lems through the pre-sentence report and Dr. Hinton’s report,
the information contained in those reports was conclusory and
based solely on Lambright’s own accounts of his history. No
medical records were offered to substantiate his reports of sui-
                     LAMBRIGHT v. SCHRIRO                 7767
cide attempts or psychiatric hospitalization, and no mental
health professional was called to testify about the extent and
nature of his mental health problems. Thus, while certain
basic information about Lambright’s mental health problems
was presented to the sentencing judge, this information was
incomplete, not compellingly presented, and buried in other-
wise damning reports.

   Moreover, because Brogna apparently failed to recognize
that Dr. Hinton’s diagnosis of antisocial personality disorder
is a mitigating factor under Arizona law, see Smith v. Stewart,
140 F.3d at 1270, he never urged the sentencing judge to give
this diagnosis mitigating weight. Indeed, Brogna never argued
that the scant mental health evidence that was before the court
should be considered in mitigation. Instead, he suggested that
Lambright did not suffer from the mental health problem
diagnosed by Dr. Hinton.

   Brogna’s failure to identify the minimal mitigating evi-
dence in the record and to urge it in mitigation likewise
applies to Lambright’s disturbed childhood and his history of
drug abuse. Brogna never pointed out to the sentencing judge
that either of these conditions constituted mitigating factors,
never urged that the judge treat them as such, and never
explained the weight that should be given them.

   We do not underestimate the importance of the role of
counsel in the adversarial process. The sentencing judge can-
not be expected to comb the record looking for mitigating fac-
tors, particularly where the minimal evidence that exists is
buried in reports that are on the whole strongly unfavorable
to the defendant. When a defense lawyer fails to identify cru-
cial mitigating factors and fails to explain why those factors
should affect the judge’s decision, that failure alone may, in
some instances, be prejudicial. To the extent that the state
argues that the minimal mitigating information that was
before the court principally as a result of the submission of
the pre-sentence report and Dr. Hinton’s report defeats Lam-
7768                  LAMBRIGHT v. SCHRIRO
bright’s claim of prejudice, we rejected that argument in Cor-
rell. There, we held that

    [w]hile the bare facts of Correll’s troubled past were
    indeed presented to the court [through the pre-
    sentence report and defense counsel’s brief sentenc-
    ing memorandum], without further investigation and
    presentation of contextual evidence and argument,
    such facts served only to demonize Correll rather
    than to mitigate the appropriateness of the death pen-
    alty for his actions.

Correll, 465 F.3d at 1015 n.5.

   [13] In sum, there is a significant quantity of “classic” miti-
gating evidence that was never presented or urged upon the
sentencing judge on account of Brogna’s failure to adequately
investigate and prepare Lambright’s sentencing defense. Had
counsel conducted a reasonable investigation with respect to
Lambright’s childhood, mental health, and history of drug
abuse, had he effectively presented the information he would
have uncovered, and had he then made the appropriate argu-
ments to the sentencing judge, there is a reasonable probabil-
ity that the result of the sentencing proceeding would have
been different; put plainly, Brogna’s failure to provide effec-
tive assistance of counsel undermines our confidence in the
result.

   [14] The prejudicial nature of Brogna’s failure to develop
and adequately present available mitigating evidence becomes
particularly “apparent when we consider the effect of the error
under Arizona law. At the time of the penalty phase proceed-
ings, Arizona law mandated the death penalty [where one or
more aggravating factors were present] . . . if there was no
mitigating evidence. . . . Thus, [a lawyer’s] failure to present
any evidence in mitigation [would] ‘all but assure[ ] the impo-
sition of a death sentence under Arizona law.’ ” Id. at 1012
(quoting Summerlin, 427 F.3d at 640); see also Smith v. Stew-
                     LAMBRIGHT v. SCHRIRO                  7769
art, 140 F.3d at 1268, 1270 (stating that, in light of Arizona’s
statute, counsel’s “few asthenic comments” at sentencing
amounted to a “virtual admission that the death penalty
should be imposed upon his client”).

   [15] The effect of Arizona’s death penalty statute is partic-
ularly striking in the case at hand given the sentencing judge’s
statements at the hearing in which he announced his penalty
verdict. In sentencing Lambright to death, the sentencing
judge stated that

    the very factors which make murder a terrible crime
    make the death penalty a terrible punishment.

       THE COURT has been asked if “justice” requires
    the maximum penalty; the question is answered by
    quoting the statute[:] “. . . The Court . . . shall
    impose a sentence of death if it finds one or more
    aggravating circumstances and finds no mitigating
    circumstances sufficiently substantial to call for
    leniency.”

      THE COURT HAS SO FOUND, and the LAW
    demands the maximum penalty . . .

(emphasis in original). Thus, the sentencing judge’s own
statements make clear that, given Brogna’s failure to present
any significant mitigating evidence, the judge felt legally
compelled to impose the death penalty in this case. Had
Brogna presented the mitigating evidence that would have
been unearthed through a reasonable investigation of the miti-
gating circumstances, there is a reasonable probability that the
result of the sentencing judge’s penalty deliberations would
have been different.

   Finally, this is not a case in which there were a multitude
of aggravating factors that Lambright would have had to over-
come in order to receive a life sentence. To the contrary, the
7770                 LAMBRIGHT v. SCHRIRO
sole aggravating factor found by the sentencing judge was the
fact that the crime here at issue was “committed in an espe-
cially heinous, cruel, or depraved manner.” As we noted in
our opinion remanding this case for an evidentiary hearing,

    [w]e have previously found that the prejudice
    requirement is met where “defense counsel effec-
    tively presented no mitigating evidence at sentenc-
    ing, despite the presence of aggravating factors.” . . .
    [I]n this case the State argued that only one aggra-
    vating factor existed. Although the offense in this
    case certainly was brutal and sadistic, the Supreme
    Court in Williams recently noted that “[m]itigating
    evidence unrelated to dangerousness may alter the
    jury’s selection of penalty, even if it does not under-
    mine or rebut the prosecution’s death-eligibility
    case.” . . . Evidence of mental disabilities or a tragic
    childhood can affect a sentencing determination even
    in the most savage case.

Lambright III, 241 F.3d at 1208 (citations omitted).

   We have held that, in light of the Supreme Court’s deci-
sions in Wiggins and Williams v. Taylor, it is clear that “the
presentation of mitigating evidence is vital even where . . . the
aggravating evidence is powerful.” Stankewitz, 365 F.3d at
714. In Ainsworth, for example, where we held that counsel’s
failure to present evidence very similar to that which should
have been presented in Lambright’s case was prejudicial, the
offense was at least as, if not more, vile than the offense at
issue here. Ainsworth, 268 F.3d at 870-71. Ainsworth
approached the victim as she sat in her parked car, and shot
her in the left hip with a .45 caliber handgun. Id. at 870. The
bullet passed through her pelvis and lodged against her right
hip. Id. During the next twenty-four hours, Ainsworth con-
fined the suffering victim within her car, ignored her pleas for
help and, at one point, put her in the trunk because he was
tired of hearing her moan and cry. Id. Then, after removing
                      LAMBRIGHT v. SCHRIRO                    7771
her from the trunk, he raped her. Id. Twenty-four hours after
she was shot, the victim finally died and Ainsworth dumped
her body and abandoned her car. Id. at 871. In spite of the
savageness of this offense, and in spite of other significant
aggravating factors present in that case, we held that Ains-
worth’s counsel’s failure to introduce available mitigating
evidence regarding “Ainsworth’s troubled childhood, history
of substance abuse, and mental and emotional problems” was
prejudicial. Id. at 875, 878.

    [16] Indeed, we have held consistently that even in cases
involving particularly heinous murders, a defendant can be
prejudiced by an attorney’s failure to investigate and present
mitigating evidence. See Hovey v. Ayers, 458 F.3d 892, 930
(9th Cir. 2006) (noting that even where a defendant has been
convicted of horrible crimes, a sentencer may still choose to
impose a life sentence when confronted with mitigating evi-
dence); Douglas, 316 F.3d at 1091 (finding that “[t]he grue-
some nature of the killing did not necessarily mean that the
death penalty was unavoidable.”); Smith v. Stewart, 189 F.3d
at 1013 (“[T]he horrific nature of the crimes involved here
does not cause us to find an absence of prejudice.”); Hen-
dricks v. Calderon, 70 F.3d 1032, 1044 (9th Cir. 1995) (con-
cluding that “despite . . . substantial evidence of aggravation,
. . . the failure . . . to present mitigating evidence rendered the
sentencing hearing neither fair nor reliable”).

   In sum, Brogna’s failure to conduct a thorough investiga-
tion of all potentially mitigating evidence was unreasonable,
especially in light of the information available to him, and fell
far below standards of professional conduct. Because the evi-
dence counsel failed to uncover and present to the sentencing
judge was highly significant, because there was but one factor
in aggravation in this case, and because Brogna’s failures
were particularly prejudicial in light of Arizona law, Lam-
bright has adequately “undermined [our] confidence in the
outcome” of the penalty phase. See Strickland, 466 U.S. at
694. For these reasons, we hold that the district court erred in
7772                     LAMBRIGHT v. SCHRIRO
finding that Lambright was not prejudiced by Brogna’s inef-
fective representation.

                           CONCLUSION

  The district court erred in concluding that Lambright did
not receive ineffective assistance of counsel at the penalty
phase of his trial and further erred in holding that, even if he
did, he suffered no prejudice as a result. The sentence
imposed is vacated. Further sentencing by the state court shall
be conducted in conformance with applicable law.

  REVERSED and REMANDED for issuance of a writ of
habeas corpus.



FERGUSON, Circuit Judge, concurring:

                                     I.

   I concur in the per curiam opinion. I write separately to
focus on the district court’s erroneous rejection of Lam-
bright’s Post Traumatic Stress Disorder (PTSD) claim.

                                    II.

   War is hell. Not only for the soldier who fights on the front
lines, but also for the military ambulance driver who must res-
cue the wounded, the mess hall cook whose friends are killed
on the battlefield, the civilian who loses a loved one, and the
augmentee who, like Lambright, runs patrol missions at an
Air Force base in a war-plagued country. Any member of the
military exposed to trauma may suffer from PTSD, regardless
of whether he or she served on the front lines or exchanged
gunfire with the “enemy.”1 See Kathleen A. Tarr, Above and
  1
    Of course, PTSD also occurs outside of the context of war. It can be
triggered by anything from domestic violence, see, e.g., M.C. Austin et al.,
                        LAMBRIGHT v. SCHRIRO                        7773
Beyond: Veterans Disabled by Military Service, 5 Geo. J.
Fighting Poverty 39, 43 (1997) (recognizing “the simple fact
that almost anyone who serve[s] during wartime [is] exposed
to stress capable of causing mental disability” and “that most
service-members’ wartime experiences [are] horrific and
potentially disabling, even if not uncommon”).

   Lambright claimed to have been involved in combat at the
Phu Cat Airbase in Vietnam while serving as an augmentee.
He testified that Viet Cong soldiers ambushed him and a
friend while they were performing police duties. Lambright
claimed that his friend died in his arms after being shot in the
stomach.

   The district court found that Lambright’s “testimony with
respect to the trauma underlying his expert’s PTSD diagnosis
(the alleged combat experience) [was] less than credible.”
While this finding is not clearly erroneous, given the exten-
sive evidence casting doubt on the specifics of Lambright’s
story, the district court did err in concluding that Lambright
therefore did not suffer from PTSD. Although Lambright’s
psychiatrist relied on the combat story in diagnosing Lam-
bright with PTSD, he also testified that Lambright’s general
Vietnam experience could have triggered the disorder and that
“merely being in a base where there was mortar fire and con-
siderable danger is also potentially enough to satisfy this diag-
nosis.”

   There is no question that Lambright came home from Viet-
nam a changed man. His first wife testified that before his
deployment to Vietnam, Lambright “was a kind person, gen-
tle, free-hearted,” but that he returned troubled and disturbed.

Posttraumatic Stress Disorder Among Battered Women: Risk and Resil-
iency Factors, 8 Violence & Victims 17 (1993), to animal abuse, see, e.g.,
Taimie L. Bryant, Trauma, Law, and Advocacy for Animals, 1 J. of Ani-
mal L. and Ethics 63 (2006).
7774                 LAMBRIGHT v. SCHRIRO
Lambright “wasn’t like the same person. . . . [H]e didn’t have
a calm nature about him. . . . [H]e wasn’t a happy person.” He
had difficulty sleeping and suffered from frequent combat
nightmares, including one incident in which he grabbed his
wife and told her to get down because the Viet Cong was hid-
ing in the bushes. Lambright often wished himself dead, and
on one occasion he drove his car into a tree in an attempt to
kill himself.

   Lambright’s sister also observed a significant change after
Lambright returned from Vietnam. She stated, “[B]efore he
went to Viet Nam[,] Joe was kind, gentle, and well-behaved.
When he got back from his service in Viet Nam he was com-
pletely changed. He was extremely tense, paranoid, and ner-
vous.” She once discovered him on her porch, “cowering
against a wall [and] swinging a butcher knife,” and hallucinat-
ing about an “imaginary attack by someone or something.”

   Given the horrors of even the most mundane aspects of the
Vietnam war, see generally, Michael Herr, Dispatches (1977),
coupled with Lambright’s marked postwar change in person-
ality and his exhibition of PTSD symptoms, it is quite likely
that Lambright was exposed to some trauma in Vietnam that
triggered PTSD, even if his Phu Cat Air Base story was a fig-
ment of his imagination.

                              III.

   The district court, having concluded that Lambright’s war
story was fabricated, should have then determined whether
Lambright’s Vietnam experience exposed him to any non-
combat stressors sufficient to induce PTSD. Were we not
reversing on other grounds, I believe the district court’s erro-
neous assumptions about PTSD would necessitate a remand
for such a determination.
