Opinion by Judge TALLMAN; Concurrence by Chief Judge KOZINSKI; Dissent by Judge FISHER.
TALLMAN, Circuit Judge:Scott Lynn Pinholster faces a death sentence in California for murdering Thomas Johnson and Robert Beckett on January 9, 1982, robbing Johnson and Beckett with intentional infliction of great bodily injury and with personal use of a knife, robbing Todd Croutch with a firearm, and burglarizing Michael Kumar’s residence. The jury found two special circumstances: Pin-holster, in the same proceeding, was convicted of more than one murder, CaLPenal Code § 190.2(a)(3) (1984), and he committed the murders during a robbery and a burglary, id. § 190.2(a)(17)(i), (vii). The jury fixed Pinholster’s penalty at death, and on June 4, 1984, the Los Angeles County Superior Court so sentenced him.
On automatic appeal, the California Supreme Court, in an opinion written by Justice Stanley Mosk, set aside one multiple-murder special-circumstance finding but otherwise affirmed the judgment. See People v. Pinholster, 1 Cal.4th 865, 4 Cal. Rptr.2d 765, 824 P.2d 571 (1992). Pinhol-ster sought a writ of habeas corpus. He challenged his convictions and death sentence. The California Supreme Court summarily denied Pinholster’s state petition for habeas corpus. Pinholster filed a federal habeas corpus petition but the district court dismissed it when the parties stipulated that the petition contained unex-hausted claims. Pinholster returned to state court to exhaust those claims. On October 1, 1997, the California Supreme Court denied Pinholster’s second habeas petition.
Pinholster then filed an amended federal habeas petition and requested an eviden-tiary hearing on several claims. The district court granted the State’s motion for summary judgment on Pinholster’s claims challenging the constitutionality of his convictions. Pinholster appeals the district court’s denial of his request for an eviden-tiary hearing on his guilt phase ineffective assistance of counsel claims. However, the district court concluded that his counsel inadequately investigated and deficiently presented mitigating evidence at the penalty phase and granted Pinholster’s ha-beas petition with respect to the death penalty. The State cross-appeals the district court’s judgment setting aside Pinhol-ster’s death sentence.
*749We affirm the district court’s denial of an evidentiary hearing on Pinholster’s claims of ineffective assistance during the guilt phase. We reverse the district court’s grant of habeas relief on Pinhol-ster’s death sentence.
I
A
On January 9, 1982, Pinholster fatally stabbed the victims, Johnson and Beckett, during Pinholster’s burglary of Kumar’s residence.1 Pinholster, 4 Cal.Rptr.2d 765, 824 P.2d at 582. Kumar was a known drug dealer and acquaintance of Pinhol-ster. Charles Kempf, another acquaintance of Pinholster, testified that in mid-December 1981, Pinholster suggested to Kempf and three others that they rob Kumar of his drug stash.2 Id. According to Kempf, Pinholster considered Kumar “an easy mark.” Id. The five went to Kumar’s home, but soon aborted the plan. Kumar was not home during the December visit, and they preferred to gain access through Kumar rather than break in. Id. Kempf testified that Pinholster carried a buck knife, and Pinholster claimed he would get Kumar’s drugs “one way or the other.” In addition, Kempf testified that Pinholster bragged about having stabbed someone in the rectum during a previous robbery. Id.
Art Corona — an accomplice in the crimes — served as the State’s primary witness. He testified that on January 8,1982, he attended a social gathering at Pinhol-ster’s apartment complex. Id. Corona agreed to help Pinholster and co-defendant Brown rob Kumar. Id. En route, Corona drove the two in his car and stopped at Lisa Tapar’s residence. Id. Pinholster wanted Tapar to help them gain access to Kumar’s residence. Id. After Tapar refused to allow Pinholster into her apartment, he used his buck knife to vandalize the door of her apartment and the hood of her car. Id. Tapar, her father, and another witness corroborated Corona’s version of this incident. The group then left Ta-par’s apartment to burglarize Kumar’s residence.
Corona testified about the events that took place during the burglary. Pinhol-ster gained entry by breaking a window in the rear of the home and Brown entered through an open sliding-glass door. Id. at 582-83. The three ransacked the house. Id. at 583. Pinholster found marijuana in a bedroom and spilled a green substance in the kitchen. Id. At this time, victims Johnson and Beckett (Kumar’s housesit-ters) arrived, opened the front door, discovered the crime, and shouted they would call the police. The three burglars attempted to leave through the rear sliding-glass door, but Johnson and Beckett came around to the back. As Johnson tried to enter, Pinholster stabbed Johnson in the chest three to four times with the knife. The California Supreme Court summarized Corona’s description of the robbery, stabbing, and murders as follows:
[Pinholster] backed [Johnson] out of the house and onto the patio, demanding drugs and money and repeatedly striking him. Johnson dropped his wallet on *750the ground and obeyed [Pinholster’s] order to sit. Then Beckett approached, and [Pinholster] attacked him. Corona saw that [Pinholster] was stabbing Beckett, striking him in the chest as Corona had seen [Pinholster] strike Johnson. [Pinholster] repeatedly stabbed Beckett, again demanding money and drugs. [Pinholster] picked up Johnson’s wallet and took a wallet from Beckett’s pocket. [Pinholster] repeatedly kicked Beckett in the head. Corona then saw codefendant Brown stabbing Johnson in the chest. The three men withdrew, and Corona drove them back to [Pinholster’s] apartment. Brown and [Pinholster] commented that they had “gotten them good,” and Brown said he had “buried his knife to the hilt” in Johnson.
Id.
After the murders, the three returned to Pinholster’s apartment and split the proceeds. Pinholster washed his knife and a woman named Debbie washed Brown’s knife. Id. The next day, Pinholster telephoned Corona and told him to “lie low.” Two weeks later, Corona turned himself in and gave a statement to the police. Corona testified at trial consistent with his earlier statement except that at trial he also mentioned seeing Brown stab Johnson and that he, Brown, and Pinholster divided the proceeds. Id.
Casey Corona, Art Corona’s wife, was at Pinholster’s apartment when Pinholster, Brown, and Art Corona returned from Ku-mar’s house. At trial, Casey corroborated Corona’s testimony about the planning, execution, and cover up of the robbery/murders. She testified that she saw Pinhol-ster wash blood off his knife and she heard him say: “It had to be done the way it was done. We had to do what we had to do.” Id. Police had recently arrested Casey on a drug charge, and she testified that the prosecution assisted her entry into a diversion program.
Art Corona also testified that Pinholster had threatened him on numerous occasions. Specifically, prior to the preliminary hearing, Pinholster threatened to “blow up” Corona on his way to court if Corona testified against him. Pinholster impeached Corona with Corona’s prior burglary conviction and Corona’s admission that he was a professional burglar. Id.
The State introduced physical evidence to corroborate Pinholster’s presence in Ku-mar’s residence after it had been ransacked. Corona testified that Pinholster wore jeans and boots on the night of the murders. Police found boots with microscopic blood stains and a towel with a blood stain in Pinholster’s apartment. Police also found a pair of jeans with a blood stain; however, investigators could not confirm whether the blood was human. In addition, when police arrested Brown, he had a buck knife with dimensions that corresponded to one of Johnson’s stab wounds. Id. at 583-84. Investigators also discovered traces of human blood near the hilt of Brown’s knife. The police found human blood on the inside forearm of the sleeve of Corona’s shirt, but they found no blood on his knife. Id. at 584.
Pinholster presented an alibi when he testified in his own defense at trial. He characterized himself as a “professional robber” who used guns while preying on drug dealers, not a murderer who used knives. He boasted of being a “very good robber,” claiming that he had committed “hundreds” of robberies and that he had only been caught by the authorities one time. To support his defense, Pinholster admitted to robbing Thomas Crouteh at gunpoint on another occasion, and having planned to rob Kumar, but denied having recruited Kempf and the three other indi*751viduals to do so. Pinholster also admitted to breaking into Kumar’s house on the night of the murders.
By way of his alibi, Pinholster claimed he had thrown a party in memory of his best friend, “Shotgun,” on the night of the murders. Id. He testified that around 8 p.m. he left the party and went to Kumar’s house, broke a window, and gained access through the kitchen. He took a bag of marijuana, touched a bluish substance in a bedroom, and spilled a bag with green material in the kitchen. He denied ransacking the house or killing anyone.3 Id. Pinholster said he had returned to his house around 9 p.m., and smoked a considerable amount of marijuana and consumed a lot of alcohol. Around 11:30 p.m., Corona asked Pinholster for an ounce of marijuana to sell. Pinholster said he gave Kumar’s address to Corona in exchange for a third of whatever drugs Corona took from Kumar’s house. Corona could not find Kumar’s residence and returned around 1 a.m. Pinholster gave him the directions again, and around 1:30 a.m. Pin-holster went to Tapar’s house to tell her that “Shotgun” had died.4 Id. at 585. He admitted to stabbing her door and carving a swastika and lightning bolt on her car after she refused to admit him. Pinholster claimed that he returned to his apartment around 2 a.m., and Corona returned around 4 a.m. Pinholster’s brother and several friends corroborated his version of the events. The superior court jury by its verdict obviously rejected Pinholster’s alibi defense.
B
The State sought the death penalty. On March 22, 1983, the prosecution mailed a California Penal Code section 190.3 letter to Pinholster at the Los Angeles County Jail, notifying him that the State intended to offer aggravating evidence at the penalty proceedings. Pinholster and his counsel 5 contended they were not informed of the letter until the guilt phase concluded on April 24, 1984. Pinholster moved to exclude aggravating evidence based on the prosecution’s failure to comply with California Penal Code section 190.3. The court denied the motion.6 Rather than move to continue the penalty phase — a request the state trial court indicated it would grant — Pinholster’s counsel (Brai-nard and Dettmar) elected to proceed. The penalty phase began on May 1, 1984. The court instructed the jury on May 2, 1984, and the jury returned a verdict of *752death on each of the two murder counts on May 7,1984.
The prosecution called eight penalty phase witnesses. First, Jack Taube, Pin-holster’s juvenile probation officer, testified that Pinholster had previously struck a bailiff without cause after a court proceeding. Several bailiffs had to physically restrain Pinholster, and, as Pinholster left the proceeding, he continued to orally threaten the wounded bailiff. Taube also testified about Pinholster’s involvement in juvenile gangs. Second, Los Angeles Police Department (“LAPD”) patrol officer David Kaufman testified that shortly after he and his partner responded to a fight involving Pinholster, Pinholster appeared to fake an epileptic seizure. Officer Kaufman also testified that once handcuffed, Pinholster became belligerent and threatened to kick the officers. After the officers transferred Pinholster to a facility for possible medical treatment, and upon removing Pinholster’s leg restraints, Pinhol-ster kicked Officer Kaufman in the head.
Third, Ernest Guzman, another LAPD officer, testified that after refusing to enter his police vehicle on a different occasion, Pinholster seemingly faked an epileptic seizure. After the officers placed Pinholster in the police car he became violent, kicking at Officer Guzman’s head. After Pinholster told the officers that he had a knee injury, they transported him to Valley Receiving Hospital for an evaluation. During that time, Pinholster spat in Guzman’s partner’s face, and refused to allow doctors to examine his knee. Pin-holster kicked and broke one of the glass panes in the x-ray machine. Fourth, Deputy Sheriff Michael Loper testified to having “numerous run-ins” with Pinholster in a Los Angeles County Jail. Pinholster struck Loper as he assisted another deputy in gaining control over Pinholster, who had refused to comply with jail rules.
Fifth, Operations Sergeant Thomas Pig-gott testified about Pinholster’s violent reputation and disciplinary record at the Los Angeles County Central Jail. He described eleven documented incidents of Pinholster’s violence or recalcitrance and stated that Pinholster had a reputation of throwing cups of urine at the deputies as they walked by his cell. Piggott also testified that he tried to counsel Pinholster, but Pinholster insisted that he wanted to go to prison. Piggott recalled Pinholster saying, “They better send me now, because if they don’t I’ll just go out on the streets and do something to get back in, go to prison.”
Sixth, Theodore Mesquita testified about fighting with Pinholster over a woman Mesquita dated, which resulted in Pinhol-ster cutting Mesquita’s arm with a straight razor, requiring approximately fifty stitches. Pinholster’s wife, Cathy Ann Smith, testified that Pinholster once broke her jaw while seeming to have an epileptic seizure. Finally, Sheriffs Sergeant Joseph Barrett testified that Pinholster told Barrett he would kill Art Corona when released from prison.
In addition, to minimize the inconvenience of gathering witnesses from San Luis Obispo, Pinholster’s counsel stipulated that (1) Pinholster’s prior kidnaping conviction involved a knife, but that no plea bargain governed the knife use allegation (Pinhol-ster admitted to carrying the knife and placing it at the victim’s throat), and (2) Pinholster committed numerous prison disciplinary infractions, including throwing urine at and threatening various corrections officers. Counsel stipulated that Pin-holster threatened to stab a corrections officer and to throw another corrections officer off of the prison tier. Pinholster’s disciplinary infractions resulted in the Director of Corrections ordering Pinholster to be placed on a special disciplinary diet for a nine-day period in 1979, a procedure *753reserved for only the most disruptive inmates.
Pinholster’s counsel, Dettmar, waived making an opening statement in the penalty phase of his trial and immediately called Pinholster’s mother, Burnice Brashear. She testified about Pinholster’s strained relationship with his step-father, Bud Brashear; Pinholster’s head injury at age two and one-half years when she ran over him with her car; his head injury shortly thereafter when his head cracked the windshield during a car accident; his disruptive behavior at school; a psychologist’s recommendation that Pinholster be committed to a mental hospital when he was ten; his time in a class for the emotionally handicapped; his view of himself as a neighborhood Robin Hood because he stole things to distribute to the neighborhood children; his frequent stays at boys’ homes, juvenile halls, and juvenile camps; and his epilepsy, which she believed resulted from a severe beating at age eighteen in county jail.
C
Following Pinholster’s unsuccessful direct appeal, he initiated habeas proceedings in state and federal court. We detail his submissions with regard to his penalty phase ineffective assistance of counsel claim because the State contends that, by the time of the federal evidentiary hearing, this claim had transmogrified into a completely new theory for which Pinholster now relies on yet a third set of mental health experts.
1
Pinholster raised fifty claims for relief in his state habeas petition. Relevant to this appeal, Pinholster claims his counsel provided ineffective assistance at the guilt and penalty phases of his trial. Regarding his death sentence, he argues that his trial counsel unreasonably failed to investigate, prepare, and present mitigating evidence, and unreasonably presented evidence that hurt his mitigation case. Had his counsel investigated mitigating evidence, he contends, his lawyers would have uncovered a wealth of mitigating evidence- — a turbulent, dysfunctional, violent and abusive home life; serious, well-documented educational disabilities; and profound mental disorders. To support this claim, Pinhol-ster submitted declarations from family members and from his trial attorney, Brai-nard; various medical, legal, and school records of Pinholster and his relatives; and a declaration obtained during habeas proceedings from psychiatrist Dr. George Woods.
Dr. Woods diagnosed Pinholster with a long standing bipolar mood disorder with psychotic features. Dr. Woods opined that, during the murders, Pinholster was substantially impaired by a bipolar mood disorder operating synergistically with a seizure disorder.7 Dr. Woods also criticized Dr. John Stalberg’s psychiatric evaluation. Dr. Stalberg had previously examined Pinholster at defense counsel’s request on March 11, 1984, after trial began. He reviewed case materials supplied by counsel, including police reports and a probation report. Dr. Stalberg concluded that Pinholster did not manifest by history any significant signs of mental disorder or defect other than Antisocial Personality Disorder.8 Dr. Stal-*754berg stated he saw no mitigating evidence, and defense counsel decided not to pursue this issue at the time. Habeas counsel disavowed Dr. Stalberg as a credible expert after retaining Dr. Woods to criticize Dr. Stalberg’s mid-trial evaluation of Pinholster.
After the parties filed briefing in the state habeas case, the California Supreme Court issued an order to show cause, but subsequently vacated it as “improvidently granted.” The court then denied the writ “on the substantive ground that it is without merit.” The California Supreme Court also denied several other claims on procedural grounds.
2
In Pinholster’s first federal habeas petition, he continued to maintain that his trial counsel unreasonably failed to investigate, prepare, and present mitigating evidence during the penalty phase. This time, however, Pinholster switched tactics and renamed Dr. Stalberg as his psychiatric expert. In April 1997, Pinholster’s habeas counsel asked Dr. Stalberg to review additional materials pertaining to Pinholster and his family. Dr. Stalberg reviewed the materials and spoke with several of Pinhol-ster’s family members. Dr. Stalberg then concluded that knowledge of Pinholster’s family history of severe psychiatric disorders, Pinholster’s disturbed behavior during childhood, and his irrational and highly aggressive actions immediately before the homicides would have caused him to inquire further before concluding that Pin-holster merely had a personality disorder. Dr. Stalberg also would have inquired further to determine if the homicides related to a mental impairment caused by organic/neurological dysfunction. Dr. Stalberg now declared that the new information he reviewed would have materially modified his previous opinion regarding mitigating circumstances, and that his review now demonstrated the existence of voluminous mitigating evidence.
Because the declaration contained new material facts, the parties stipulated that certain claims, including the penalty phase ineffective assistance of counsel claim, were unexhausted. The district court allowed Pinholster to exhaust the claims in state court.
3
Pinholster filed a copy of his federal petition and Dr. Stalberg’s new declaration in the California Supreme Court. The court denied Pinholster’s petition “on the substantive ground that it was without merit” and denied other claims on procedural grounds.
4
Pinholster filed a “First Amended Petition for Writ of Habeas Corpus” in federal court on November 14, 1997. On April 13, 1999, Pinholster filed a request for a federal evidentiary hearing. Applying pre-Anti-terrorism and Effective Death Penalty Act (“AEDPA”) standards, the district court granted an evidentiary hearing on Pinhol-ster’s penalty phase ineffective assistance of counsel claim, and two other claims not relevant to this appeal.9
*755Dr. Stalberg anticipated testifying as a witness at the federal evidentiary hearing. Pinholster submitted two new declarations from Dr. Stalberg to support his amended federal habeas petition. The first, dated January 24, 2000, explained that it was Dr. Stalberg’s custom and practice in 1984 when retained by defense counsel in a capital case to form an opinion about a defendant’s mental state during the offense and to identify mitigating circumstances. The second, dated June 5, 2001, expanded upon and specified the factual bases for the opinions Dr. Stalberg previously presented to the district court. In July 2001, the State Attorney General’s Office deposed Dr. Stalberg. The Deputy Attorney General questioned Dr. Stalberg about his earlier declarations, and Pinhol-ster’s counsel asked Dr. Stalberg to elaborate on various aspects of his opinions, and to express his opinions about Pinholster’s mental health.
Dr. Stalberg testified that the additional materials he reviewed did not alter his conclusion that Pinholster suffers from Antisocial Personality Disorder. As a result of this damaging testimony, on May 9, 2002, Pinholster’s current counsel, the Federal Public Defender, advised Dr. Stal-berg that he would no longer call him as a witness during the evidentiary hearing, and he no longer considered Dr. Stalberg to be Pinholster’s expert.
The district court nonetheless proceeded with an evidentiary hearing in September 2002. The Federal Public Defender’s Office now utilized two new experts — Dr. Sophia Vinogradov and Dr. Donald Olson — to bolster Pinholster’s penalty phase ineffective assistance of counsel claim. Dr. Vinogradov and Dr. Olson both submitted declarations as direct testimony at the evi-dentiary hearing. Dr. Vinogradov concluded that Pinholster suffered “personality change, aggressive type, due to serious childhood head trauma.” Dr. Olson, a pediatric neurologist, testified that Pinholster likely suffered brain damage from two head injuries in his early childhood, which created a risk of epilepsy.
On March 25, 2003, the district court granted Pinholster’s habeas petition and vacated his death sentence. The district court noted that Pinholster’s attorneys admitted they had not “prepared any evidence by way of mitigation,” yet trial counsel declined an offer for a penalty phase continuance to prepare extenuating evidence. The district court further reasoned that trial counsel called one witness — Pin-holster’s mother — -and her testimony was damaging, incomplete, and inaccurate. The district court found Pinholster’s attorneys’ performance deficient because they failed to adequately investigate mitigating evidence and lacked a reasonable strategic decision for their failure. The district court ultimately found prejudice based on the significant evidence of Pinholster’s childhood abuse and mental impairments, combined with the prosecutor’s emphasis during summation on the lack of mitigating evidence and the length of the jury’s deliberations.
The district court revisited its March 25, 2003, Order Granting Writ of Habeas Corpus, after determining that AEDPA applied under Woodford v. Garceau, 538 U.S. 202, 123 S.Ct. 1398, 155 L.Ed.2d 363 (2003). The Supreme Court filed Wood-ford on the same day the district court had filed its Order. The district court nonetheless concluded that: (1) Pinholster timely filed his federal habeas petition; (2) *756Pinholster was entitled to an evidentiary hearing under AEDPA; and (3) AEDPA did not affect its Order granting Pinholster habeas relief because the California Supreme Court “did not adjudicate Pinhol-ster’s claim that counsel was ineffective for failing to investigate and present mitigating evidence at the penalty phase.”
II
We review de novo the district court’s decision to grant or deny a petition for writ of habeas corpus. Lambert v. Blodgett, 393 F.3d 943, 964 (9th Cir.2004). We review factual findings and credibility findings made in the context of granting or denying the petition for clear error. Id.
Neither party disputes that AEDPA now governs Pinholster’s petition. AEDPA requires us to defer to the state court’s determination of federal issues, unless that determination resulted in a decision that was contrary to, or involved an unreasonable application of, clearly established federal law, as determined by the Supreme Court. 28 U.S.C. § 2254(d)(1).10 Deference to state court decisions applies only to claims the state court adjudicated on the merits.11 Lambert, 393 F.3d at 965. De novo review applies if the state court did not reach the merits of a particular issue. Lewis v. Mayle, 391 F.3d 989, 996 (9th Cir.2004).
A decision is “contrary to” federal law when the state court applies a rule of law that contradicts the governing law set forth in Supreme Court precedent or when the state court makes a determination contrary to a Supreme Court decision on materially indistinguishable facts. Williams v. Taylor, 529 U.S. 362, 405-06, 120 S.Ct. 1495, 146 L.Ed.2d 389 (2000). A state court unreasonably applies federal law when its application of Supreme Court precedent to the facts of petitioner’s case is objectively unreasonable. Id. at 409, 120 S.Ct. 1495.
Ill
We first address Pinholster’s appeal of the district court’s grant of summary judgment in favor of the State on his claims of ineffective assistance of counsel during the guilt phase of his trial. Pinhol-ster seeks an evidentiary hearing, arguing that he has provided a colorable claim that his counsel performed deficiently. His primary contention is that his counsel failed to adequately investigate the State’s physical evidence placing him at the scene during the murders and this resulted in an *757uninformed decision to have Pinholster testify in his own defense. See United States v. Curtis, 742 F.2d 1070, 1076 (7th Cir.1984) (per curiam) (“When a defendant asserts that he desires to exercise his constitutional right to testify truthfully, counsel’s duty is to inform the defendant why he believes this course will be unwise or dangerous.”).
At the time the California Supreme Court rendered its last decision— October 1, 1997 — the Supreme Court’s two-part standard for analyzing ineffective assistance of counsel was clearly established law. See Strickland v. Washington, 466 U.S. 668, 687, 104 S.Ct. 2052, 80 L.Ed.2d 674 (1984). To establish a Sixth Amendment violation, Pinholster had to show that: (1) his counsel’s performance was deficient, i.e., it fell below an objective standard of reasonableness, and (2) the deficient performance prejudiced him. Id. In reviewing counsel’s performance, we “must be highly deferential” and should make every effort “to eliminate the distorting effects of hindsight.” Id. at 689, 104 S.Ct. 2052. Even if we conclude that counsel performed deficiently, to obtain relief the “defendant must show that there is a reasonable probability that, but for counsel’s unprofessional errors, the result of the proceeding would have been different. A reasonable probability is a probability sufficient to undermine confidence in the outcome.” Id. at 694, 104 S.Ct. 2052.
A
To satisfy the first prong of Strickland, Pinholster must “identify[ ] the acts or omissions ‘that are alleged not to have been the result of reasonable professional judgment.’ ” Earp v. Ornoski, 431 F.3d 1158, 1173-74 (9th Cir.2005) (quoting Strickland, 466 U.S. at 690, 104 S.Ct. 2052). The State offered during its casein-chief the following pieces of physical evidence to corroborate Corona’s testimony and place Pinholster at the scene of the crime at the time of the murders: (1) investigators found dried blood on the bottom of the boots taken from Pinholster’s closet and the sole print matched a bloody boot print near the victims’ bodies; and (2) investigators found a palm print matching Pinholster’s print located within the Ku-mar residence.12 Pinholster contends that trial counsel’s failure to investigate this evidence constituted deficient performance, leading to an ill-advised decision to have Pinholster testify in his own defense, during which he admitted to several incriminating facts.
1
Assuming trial counsel’s failure to investigate the physical evidence fell below the objective standard of reasonableness, we nevertheless conclude that the district court properly granted the State’s motion for summary judgment because Pinholster failed to raise a colorable claim that the deficient performance prejudiced him. See Strickland, 466 U.S. at 697, 104 S.Ct. 2052 (stating that a court may presume ineffective assistance to dispose of a claim on prejudice grounds).
*758At the homicide scene, the police detectives discovered boot prints left in blood near the victims’ bodies. When executing the search warrant for Pinholster’s apartment, homicide detectives found a pair of black boots that appeared to have tread marks that were similar to the prints left at the scene. Testing revealed microscopic stains on the boots that gave positive reactions for blood. Specifically, investigators detected blood in all of the crevices of the right boot. Criminalist Steven Schliebe also testified that the treads on the boots taken from Pinholster’s apartment were consistent with the treads that left the boot prints at the crime scene.
During cross-examination of Detective Coffey — the detective who discovered the boots in Pinholster’s apartment — Pinhol-ster’s counsel asked whether the boots had a common tread. The detective responded, “I’m not a boot expert, but I had not seen this type of tread on boots. I have seen other types of tread. Not to say it’s not common or uncommon. To me, I have not seen that type of tread before.” In his habeas petition, however, Pinholster offered a declaration from Criminalist Schliebe that stated otherwise: Schliebe declared that, “had he been asked if the sole pattern[of Pinholster’s boots and the boot prints found at the crime scene were] common in the Southern California area,” he would have answered, “the shoe sole pattern is fairly common and is frequently found on work and sport boots.”
The district court denied Pinholster’s claim of ineffective assistance of counsel for lack of prejudice. It reasoned that “the boot that was found in [Pinholster’s] home had a trace of blood on it[,] which distinguishes it from other boots with the same tread.” The district court also denied Pinholster’s claim that trial counsel were ineffective for eliciting Detective Coffey’s opinion that the boot print was uncommon. It reasoned that Detective Coffey “never testified that the boot print was uncommon”; rather, he “stated that he had not seen the sole pattern before” and “clarified that he was not a boot print expert.”
The second piece of physical evidence was a palm print lifted from a closet door frame in the Kumar residence that matched a palm print later taken from Pinholster. During direct examination, the fingerprint expert testified that he conducted two prior identification attempts before he was able to conclusively determine that the print lifted from the door matched Pinholster’s. The expert explained that the palm print lifted from the closet door came from the far outside portion of the left palm. In the two prior attempts, the lab used exemplar cards that excluded the outside portion of the palm. Normally, when a person is palm printed, the palm is laid flat on the exemplar card. Therefore, as the expert testified, “it was not until [Detective] Coffey provided [his] office with this exemplar card with the palm prints, and also a roll of the far left-hand side, that [he was] able to find the area that matched up with the print that [he] lifted from the door frame.”
Pinholster argues that his trial counsel were ineffective for failing to independently test the palm print. In support of his argument, Pinholster offered a declaration of an independent fingerprint expert, Clarence Collins. After examining both the lifted print and the rolled palm print taken from Pinholster, Collins concluded that the prints “were not made by the same person.” In addition, Pinholster offers a declaration taken from Brainard stating that, “[h]ad I known Scott Pinholster did not deposit the latent print found at the Ku-mar residence, I would have conducted the defense differently, and would have appropriately changed my advice to my client. I *759probably would have advised Scott Pinhol-ster not to testify during [the] guilt phase.”
The district court denied Pinholster’s request for an evidentiary hearing on the basis that he again failed to show prejudice. First, Pinholster admitted that he was inside Kumar’s residence on the night of the murders. Second, Pinholster’s trial counsel merely stated that he probably would have advised Pinholster not to testify.13 This does not necessarily show that Pinholster’s admission would not otherwise have been made. The record is quite clear that Pinholster was eager to take the stand so he could convince the jury that, although he saw himself as a professional thief who preyed on drug dealers, his mo-dus operandi was to carry a gun, not to stab his victims with knives.
We agree with the district court and hold that Pinholster failed to show a color-able claim that he was prejudiced by trial counsel’s alleged failure to independently investigate the State’s physical evidence. Despite Pinholster’s contention, Collins’s declaration does not prove that the State’s fingerprint expert was lying or misinformed. At most, it creates a battle of the experts.14 Moreover, the jury heard the State’s fingerprint expert testify that he could not match Pinholster’s print until the third attempt. Although Pinholster argues that the “State’s expert was pressured to find a match,” no evidence supports such a contention. In addition, the State presented the palm print evidence to place Pinholster in the Kumar residence at the time of the murders. This evidence was cumulative as Corona testified that Pinholster was in the Kumar residence at the time of the murders, and substantial portions of Corona’s testimony were corroborated by Lisa Tapar, her father, and Casey Corona. Pinholster’s admission to the jury that he was inside Kumar’s house at some point that night further convinces us that the alleged ineffectiveness did not prejudice him. Therefore, we hold that the jury’s verdict would not have been affected even if Pinholster’s trial counsel had conducted an independent investigation and introduced evidence that the palm print was not Pinholster’s.
Pinholster also failed to show a colorable claim that he was prejudiced by trial counsel’s failure to investigate the boot prints. The State did not argue that this evidence connected Pinholster to the crime because the sole prints were unique; rather, the state argued that this evidence connected Pinholster to the crime scene because (1) the sole prints were consistent, and (2) Pinholster’s boots were found to have traces of human blood on the bottom. *760Therefore, even if the jury heard evidence that the sole prints were common in Southern California, this would not have changed the verdict. Pinholster offers no other evidence to suggest that the boot print evidence was faulty.
2
Because we conclude that Pinhol-ster failed to raise a colorable claim that he was prejudiced by trial counsel’s failure to investigate the State’s physical evidence, we cannot conclude that trial counsel’s decision to advise Pinholster to testify in his own defense amounted to ineffective assistance. The dissent is ensnared in the trap of 20/20 hindsight. It fails to give a sufficient level of deference to counsel’s judgments given the evidence and the type of defense Pinholster wanted to pursue. See Rompilla v. Beard, 545 U.S. 374, 381, 125 S.Ct. 2456, 162 L.Ed.2d 360 (2005) (“In judging the defense’s investigation, as in applying Strickland generally, hindsight is discounted by pegging adequacy to counsel’s perspective at the time investigative decisions are made and by giving a heavy measure of deference to counsel’s judgments.” (internal quotation marks and citation omitted)).
“An accused’s right to testify is a constitutional right of fundamental dimension.” United States v. Joelson, 7 F.3d 174, 177 (9th Cir.1993). When reviewing ineffective assistance of counsel claims that question the attorney’s trial strategy, it is important to “note that a defendant’s Sixth Amendment rights are his alone, and that trial counsel, while held to a standard of ‘reasonable effectiveness,’ is still only an assistant to the defendant and not the master of the defense.” Mulligan v. Kemp, 771 F.2d 1436, 1441 (11th Cir.1985). The reasonableness of counsel’s chosen trial strategy depends critically “on informed strategic choices made by the defendant and on information supplied by the defendant.” Strickland, 466 U.S. at 691, 104 S.Ct. 2052. The record amply demonstrates that this strategic tactical decision was deliberate and considered. Pinholster actively participated in all key decisions, as he represented himself pro se at one point before the trial, and strongly directed the strategy he wished counsel to pursue.
The record shows that Pinholster directed his trial counsel to pursue an alibi defense on his behalf. On June 24, 1983, the trial court held a hearing on a motion to dismiss filed by Pinholster while representing himself. Pinholster argued that his first appointed trial counsel, Marvin Part, coerced him into waiving his right to a speedy trial. During the hearing, Pin-holster called Part to testify, waiving his attorney-client privilege. Pinholster questioned why Part refused to interview possible alibi witnesses in the face of physical evidence linking Pinholster to the crime scene. Pinholster’s insistent decision to pursue an alibi defense necessarily impacted his counsel’s trial strategy.15
Even without the physical evidence, the State presented overwhelming evidence that Pinholster was at the Kumar residence on the day of the murders. Corona’s testimony not only placed Pinholster at the scene during the murders, but it also detailed Pinholster’s participation in *761the murders. Several other witnesses corroborated Corona’s testimony.
In light of the evidence placing Pinhol-ster at the scene, Pinholster’s failure to show prejudice from his trial counsel’s failure to investigate the physical evidence, and Pinholster’s strong desire to pursue an alibi defense, we cannot second guess trial counsel’s decision to advise Pinholster to testify.16 In Strickland, the Court recognized that “[cjounsel’s actions are usually based ... on informed strategic choices made by the defendant and on information supplied by the defendant.” 466 U.S. at 691, 104 S.Ct. 2052. To support Pinhol-ster’s alibi defense, trial counsel needed to explain the overwhelming evidence proving that Pinholster intended to rob the Kumar residence on the night of the murders. In other words, counsel needed Pinholster to tell his version of the events — that he was a robber, not a burglar, and that he used guns, not knives. Given the evidence presented by the State, trial counsel’s tactical decision to advise Pinholster to testify was reasonable. Sec id. Such a decision does not amount to constitutionally deficient performance. To declare that it was wrong because in hindsight it proved unsuccessful and must have been uninformed is not what the Supreme Court intended when we analyze a Strickland claim after the fact.
B
We also conclude that Pinholster has failed to present a colorable claim that he was prejudiced by the other alleged instances of ineffective assistance of counsel during the guilt phase of his trial.
1
One alleged instance concerned Art Corona’s police interview. Through stipulation of counsel, the State introduced the unredacted tape recording and transcription of Corona’s police interview. During the interview, Corona claimed that Pinholster admitted involvement in the shooting of two “wetbacks,” that he had beaten an elderly woman, was involved in a cocaine “rip-off,” sold drugs, committed robberies, and had affiliated with white supremacist prison gangs.17
The California Supreme Court rejected Pinholster’s ineffective assistance of counsel claim, concluding that trial counsel had a “rational tactical reason” for deciding not to object to admission of the entire interview. Pinholster, 4 Cal.Rptr.2d 765, 824 P.2d at 604.18
The court reasoned that “[Pinholster] needed to create an impression of candor to carry his testimony that he had broken into the Kumar house on the night of the murder[s], but had stolen the drugs and left before Corona arrived and stabbed the murder victims.” Id. Pinholster himself testified about his violent criminal past and the references that Corona made to specific instances “simply confirmed what[Pin-*762holster] was willing to say about himself.” Id.
The California Supreme Court called Corona’s reference to the Aryan Brotherhood “clearly innocuous,” as Corona testified that it was Brown who was affiliated with the group, not Pinholster. Id. Moreover, the interview could reasonably be seen as favorable to Pinholster’s defense. “[T]he tape contained statements inconsistent with Corona’s trial testimony, showed Corona’s eagerness to cooperate with the police, and contained some reference to Corona’s contact with one ‘Butch,’ who [Pinholster] claimed was Corona’s actual accomplice.” Id. The district court denied Pinholster’s motion for an evidentiary hearing because certain aspects of the tape were “beneficial to Pinholster’s case” and therefore trial counsel “arguably were not deficient for failing to object to it.” The district court concluded that admitting the tape was not prejudicial because the case against Pinholster was strong and the prosecution successfully discredited his defense.
Whether counsel’s actions constituted a “tactical” decision is a question of fact, and we must decide whether the state court made an unreasonable determination of the facts in light of the evidence before it. See Edwards v. Lamarque, 475 F.3d 1121, 1126 (9th Cir.2007) (en banc) (citing Taylor v. Maddox, 366 F.3d 992, 999-1000 (9th Cir.2004)). For the reasons expressed by the district court, we hold that the California Supreme Court’s conclusion that counsel made a tactical decision to admit the entire tape was not an unreasonable determination of fact. Accordingly, the court’s conclusion that counsel made a reasonable decision was not objectively unreasonable. See id. (stating that the “reasonableness of counsel’s decision is best described as a question of law”).
2
Pinholster also claims his counsel were ineffective in failing to object to Detective Coffey’s testimony. Detective Coffey testified that Terry Pinholster, Pinholster’s brother, said Scott Pinhol-ster’s arrest was “no big deal” because his brother had been arrested for murder before. Pinholster argues that because he had never before been arrested or charged with murder, his trial counsel had no tactical basis for failing to object to this statement. The district court granted summary judgment to the State on this issue, concluding that Pinholster had failed to show prejudice as the jury had “already heard that [Pinholster] was involved in a shoot-out in which two ‘wetbacks’ had been killed. The jury could easily have surmised that [Pinholster] was arrested for murder as a result of that incident.”
Trial counsel’s failure to object to this evidence raises concerns: The portion of the Corona tape discussing the “wetback” murders and the hearsay statement of Pin-holster’s brother undermine the heart of Pinholster’s defense — that he is a robber not a murderer. Nevertheless, because the California Supreme Court’s decision regarding the Corona tape was objectively reasonable, it cannot be said that Pinhol-ster suffered prejudice from admission of his brother’s statement. As the district court reasoned, it is likely the jury put the two together, making his brother’s statement no more prejudicial than admission of the “wetback” statement.
3
Pinholster contends that his trial counsel were ineffective by admitting into evidence a prior felony conviction for kid-naping after the trial court granted a motion in limine to prohibit the State from using the evidence on cross-examination. *763In a declaration filed with Pinholster’s state and federal habeas petitions, Brai-nard admitted that he “d[id] not recall why [he] elicited Scott Pinholster’s kidnapping conviction after the court ruled that this conviction was inadmissible for impeachment purposes.”
Brainard’s question opened the door for the prosecution to question Pinholster about prior offenses in which he used a knife rather than a gun. The trial court— without objection from Pinholster’s attorneys — allowed the State to recall Pinhol-ster to the stand and question him as to whether he used a knife during the course of the kidnaping. Pinholster testified that he pled guilty to using a knife but denied actually having used the knife during the commission of the offense. Although use of a knife is alleged in the criminal information, it was not a term of the plea agreement.19 Brainard filed a declaration stating that he could “not recall whether [he] knew the knife enhancement allegation was not found true.”
We hold that Pinholster has failed to show a colorable claim that he was prejudiced by his trial counsel’s allegedly deficient performance. The jury heard other evidence that Pinholster possessed knives, including his own admission that he used a buck knife to vandalize Lisa Tapar’s car on the night of the murders. The district court properly denied Pinholster an evi-dentiary hearing on this ineffective assistance of counsel claim.
4
Charles Kempf testified that during an aborted robbery attempt at Ku-mar’s residence Pinholster bragged about stabbing an unidentified individual in the rectum. Pinholster contends that his trial counsel were ineffective for failing to object to Kempfs statement and failing to impeach Kempf with a prior statement in which he claims that Pinholster’s friend did the stabbing.
Pinholster cannot make out a colorable claim that he was prejudiced by the admission of this evidence. During his own testimony, which was dramatic and unusual in the candor Pinholster displayed in bragging about his life of crime, Pinholster admitted to several violent acts and the evidence presented against him was overwhelming. The California Supreme Court so found, see Pinholster, 4 Cal.Rptr.2d 765, 824 P.2d at 601, 604, and we cannot say that the district court erred by failing to grant an evidentiary hearing.
5
During rebuttal, Eric Klemetti testified that he purchased marijuana from Johnson at the Kumar residence around 9 p.m. on the night of the murders. To impeach his credibility, Pinholster’s trial counsel asked Klemetti whether he had ever committed a burglary with Pinholster, and whether, he had acted as an informant during that case. Pinholster argues that this amounted to ineffective assistance because the conviction undercut his testimony that he committed robberies rather than burglaries and was otherwise inadmissible.
We agree with the district court. Trial counsel made a rational tactical decision to impeach Klemetti’s testimony with this evi*764dence as the witness would have otherwise gone unchallenged. Moreover, Pinholster failed to show prejudice because he had already admitted that he burglarized Ku-mar’s residence on the night of the murders.
6
Pinholster challenges his trial counsel’s decision to admit evidence that the police had recovered narcotics during the search of his apartment. He also claims ineffective assistance due to his trial counsel’s failure to exclude evidence that he had thrown a gun from the window of a different apartment while the police executed a search warrant on his apartment. Although his trial counsel challenged the officers’ identification of Pinholster, Pin-holster admitted during cross-examination that he threw the gun.
The district court concluded that (1) Pin-holster failed to show prejudice, as he admitted to using drugs and possessing guns in his testimony; (2) that even without Pinholster’s testimony, the narcotics evidence was not prejudicial, as the jury heard from other sources, including Corona, that Pinholster used drugs; and (3) that though trial counsel attempted to challenge the officers’ identification of Pin-holster as the man who threw the gun, it is reasonable to believe that the jury found the officers’ testimony credible. We agree and hold that the district court properly denied Pinholster’s request for an eviden-tiary hearing.
7
Pinholster argues that trial counsel were ineffective for asking prospective jurors questions about white supremacist gangs such as the Aryan Brotherhood. The district court concluded that trial counsel were not deficient because they knew the Corona tape contained references to the Aryan Brotherhood, and they made a tactical decision to forewarn the jurors that the subject might arise. On appeal, Pinholster argues that trial counsel were ineffective for failing to object when the prosecution returned to this theme throughout the guilt phase of the trial.
Pinholster has again failed to make a colorable claim that he was prejudiced by the alleged deficient performance. Given the strong evidence against Pinholster, it is not reasonably probable that trial counsel’s failure to exclude all references to Pinholster’s connection to white supremacists affected the verdict.
IV
We now turn to the State’s appeal. The State contends that the district court improperly found, based on evidence not before the state court, that Pinholster’s trial counsel inadequately investigated and deficiently presented mitigating evidence at the penalty phase. We hold that Pinholster properly exhausted his ineffective assistance of counsel claim, and that any error the district court may have committed in holding an evidentiary hearing is harmless because, even with the evidence presented at the hearing, Pinholster has not shown that he was prejudiced by counsel’s failure to offer additional mitigating evidence.20
*765A
A state prisoner must exhaust all available remedies in state court before a federal court may grant him habeas relief. 28 U.S.C. § 2254(b)(1)(A); O’Sullivan v. Boerckel, 526 U.S. 838, 842, 119 S.Ct. 1728, 144 L.Ed.2d 1 (1999). A state prisoner must describe the operative facts and federal legal theory on which he grounds his claim so the state court has a “ ‘fair opportunity’ to apply controlling legal principles to the facts bearing upon his constitutional claim.” Anderson v. Harless, 459 U.S. 4, 6, 103 S.Ct. 276, 74 L.Ed.2d 3 (1982) (per curiam) (quoting Picard v. Connor, 404 U.S. 270, 276, 92 S.Ct. 509, 30 L.Ed.2d 438 (1971)). Presenting additional facts to the district court does not evade the exhaustion requirement when the prisoner presents the substance of his claim to the state courts. See Vasquez v. Hillery, 474 U.S. 254, 257-58, 260, 106 S.Ct. 617, 88 L.Ed.2d 598 (1986) (rejecting challenge to new evidence because it did not fundamentally alter the legal claim the state courts previously considered).
We review de novo whether Pin-holster failed to exhaust California remedies. See Castillo v. McFadden, 399 F.3d 993, 998 (9th Cir.2005). The California Supreme Court had a sufficient opportunity to hear Pinholster’s claim of ineffective assistance of counsel at the penalty phase. Throughout the habeas proceedings, Pin-holster has continued to press the same legal claim (ineffective assistance at the penalty phase) and the same factual basis (e.g., counsel failed to present significant mitigating evidence and, instead, presented harmful, false evidence at the penalty phase). The federal and state petitions detail many identical facts. Both describe trial counsel’s failure to seek a continuance to prepare for the penalty phase; counsel’s introduction of Mrs. Brashear’s testimony; Pinholster’s childhood home life; and Pin-holster’s background, including his educational, medical, psychological, social, and family history. Pinholster did not, as the State contends, “present vague and conclu-sory constitutional claims in the state court, phrased with sweeping generality and supported by skimpy factual allegations.”
Though during the proceedings Pinhol-ster relied on different experts with differing mental impairment theories, the evolving theories have not significantly changed the evidentiary basis for his arguments. These experts relied on the same background information Pinholster presented to the state court, and their testimonies represent only a fragment of the mitigating evidence submitted in the state habeas proceedings. Accordingly, the facts adduced at the evidentiary hearing have not fundamentally altered the legal claim the California Supreme Court already considered and rejected, and we conclude that Pinholster has exhausted this claim. See Weaver v. Thompson, 197 F.3d 359, 364 (9th Cir.1999) (rejecting exhaustion argument as “unwarranted hairsplitting” where at each step the legal claim remained the same, but the precise factual predicate for the claim changed after the evidentiary hearing).
B
Habeas relief is proper if the California Supreme Court’s decision was either “contrary to, or involved an unreasonable application of’ Strickland.21 *766Williams, 529 U.S. at 391, 120 S.Ct. 1495 (internal quotation marks omitted). We need not determine whether Pinholster’s trial counsel performed deficiently because we find the prejudice inquiry dispositive. See Strickland, 466 U.S. at 697, 104 S.Ct. 2052 (“[TJhere is no reason ... to address both components of the inquiry if the defendant makes an insufficient showing of one. In particular, a court need not determine whether counsel’s performance was deficient before examining the prejudice suffered by the defendant as a result of the alleged deficiencies.”).
Pinholster bears the “heavy burden” of establishing actual prejudice. See Williams, 529 U.S. at 394, 120 S.Ct. 1495 (internal quotation marks omitted). He must demonstrate that there is a reasonable probability the sentencer would have found death unwarranted absent his counsel’s errors. Strickland, 466 U.S. at 695, 104 S.Ct. 2052. “A reasonable probability is a probability sufficient to undermine confidence in the outcome. [I]t is insufficient to show only that the errors had some conceivable effect on the outcome of the proceeding, because virtually every act or omission of counsel would meet that test.” Williams, 529 U.S. at 394, 120 S.Ct. 1495 (quoting Strickland, 466 U.S. at 693-94, 104 S.Ct. 2052 (citation omitted)). In Wiggins v. Smith, 539 U.S. 510, 123 S.Ct. 2527, 156 L.Ed.2d 471 (2003), the Supreme Court explained that we must reweigh the evidence in aggravation against the totality of available mitigating evidence to assess prejudice. Id. at 534, 123 S.Ct. 2527. In so doing, “we evaluate the totality of the evidence — ‘both that adduced at trial, and the evidence adduced in the habeas proceeding[s].’ ” Id. at 536, 123 S.Ct. 2527 (emphasis omitted) (quoting Williams, 529 U.S. at 397-98, 120 S.Ct. 1495).22
The dissent relies heavily on the Supreme Court’s decisions in Williams, Wiggins,23 and Rompilla. However, as Justice O’Connor stated in her concurrence in Rompilla, we must apply a “case-by-case approach to determining whether an attorney’s performance was unconstitutionally deficient under Strickland.” Rompilla, 545 U.S. at 393-94, 125 S.Ct. 2456 (O’Con-nor, J., concurring). The Supreme Court has not gone so far as to say that an attorney’s failure to uncover a certain class of mitigating evidence automatically results in a showing of prejudice. See id. Therefore, we must conduct an independent review of the evidence presented, reweighing what the State produced in the form of aggravating evidence against that which Pinholster produces in mitigation. Like the California Supreme Court, we conclude that the potential mitigating evidence is insufficient to outweigh the overwhelming aggravating evidence. We are *767heavily influenced by the damage Pinhol-ster did to himself when he took the stand in the guilt phase and testified to an unrepentant life of violent crime.
During the state and federal habeas proceedings, Pinholster submitted evidence to the state court showing that he suffered years of significant neglect and physical and emotional abuse as a child. Pinhol-ster’s step-father, Bud Brashear, frequently beat Pinholster with his fists, a belt, or anything else available, including a two-by-four board. Moreover, Pinholster presented evidence during the habeas proceedings that, because he resembléd his biological father, he was severely beaten by his grandparents.
Pinholster painted somewhat of a different picture during a July 16, 1991, interview with a defense investigator Sheryl Duvall, who at the time worked as an independent Criminal Justice Consultant. She was hired by an attorney named Leonard Tauman to prepare a social history on Pinholster. As reflected in her interview notes, Pinholster discussed his social history, including his relationship with various family members.24 Pinholster rejected his mother’s claim that his step-father “abused” him growing up. Although he admitted that his step-father used a homemade paddle freely on him and his brothers, Pinholster claimed that they “benefited” from the “discipline.” Pinholster’s primary complaint about his step-father was that “he didn’t seem to want the kids around.”
Although Pinholster presented evidence of physical abuse from his maternal grandmother, Pinholster claimed that he and his maternal grandfather were very close. He spent summers with his grandparents, working on their chicken farm. He claimed that his “[grandfather] was affectionate with the boys. He made them work hard on the farm but he was quick to praise their efforts.” Pinholster’s grandfather made him feel good about himself. When Duvall asked Pinholster whether he believed his life would have been different had his grandfather lived, Pinholster responded “definitely.” He claimed that, after his first arrest, he would have been sent to live with his grandparents. These sentiments were supported in a medical report developed upon Pinholster’s release from the Camarillo State Hospital in 1971 when Pinholster was eleven-years-old. Pinholster was reported as being “very close” to his maternal grandfather, with his grandfather’s death being an “emotional shock.”
During the interview with Duvall in 1991, Pinholster also described his relationship with his mother, Mrs. Brashear. He claimed that he always “felt very close to his mother,” and he had nothing but praise for her. He stated that “[s]he’s always been supportive of all the kids. She’s always the first there and last to leave. She always had a hot dinner on the table.” At the time of the interview, Pin-holster remained in close contact with his *768mother.25
In addition, the jury did hear some mitigating evidence from Pinholster’s mother during her penalty phase testimony. We recognize that Mrs. Brashear inaccurately portrayed herself as a dedicated, caring mother, and, indeed, she failed to present Pinholster’s troubled childhood and mental and emotional problems in the most compelling manner. Nonetheless, the jury heard mitigating facts from her testimony. Mrs. Brashear described Pinholster’s strained relationship with his step-father, conceding that Bud Brashear’s attempts to discipline Pinholster sometimes rose to the level of abuse.
On cross-examination, she admitted that her daughter, Tammy Brashear, was currently on probation, and that her other son, Alvin Pinholster, died after attempting to evade the authorities. Mrs. Brash-ear recounted an accident when she ran over Pinholster (who was a toddler) with her car, nearly tearing off one of Pinhol-ster’s ears and causing a shoulder injury that required just over a week in the hospital. She also discussed Pinholster’s second head injury resulting from another car accident; a psychologist’s recommendation to commit Pinholster to a mental hospital at age ten; his time in a class for emotionally handicapped children; and his epilepsy, which she believed resulted from a severe beating at age eighteen in county jail. The penalty phase verdict reflects the jury’s obvious rejection of such mitigating circumstances in light of all that Pinholster had said and done as a recidivist and the brutality of these robbery/murders.
It is unlikely Pinholster’s evidence of mental impairment would have had a significant impact on the jury. As a toddler, Pinholster was in two separate car accidents that allegedly resulted in head injuries, and throughout his childhood and early adolescence, Pinholster displayed symptoms of and received treatment for epilepsy. Nevertheless, the experts’ opinions about Pinholster’s psychological impairments and whether these impairments resulted from a head injury have varied considerably, becoming somewhat of a moving target for the California Supreme Court and federal courts on habeas review.
The California Supreme Court has denied two habeas petitions, one in which Pinholster relied on Dr. Woods as his expert, and another in which he relied on Dr. Stalberg as his expert. Dr. Woods opined that, during the murders, Pinholster was substantially impaired by a bipolar mood disorder operating synergistically with a seizure disorder. Declining to present Dr. Woods’s diagnosis,26 Pinholster rehired Dr. *769Stalberg as his expert for the second state habeas petition. Dr. Stalberg stated that he had reviewed the materials presented by Pinholster’s habeas counsel and that, had he known of “Pinholster’s family history of severe psychiatric disorders, his disturbed behavior during childhood, and his irrational and highly aggressive actions immediately before the homicides,” he would have “ma[de] further inquiry before concluding that [Pinholster] had merely a personality disorder.” He further stated that “[t]he new material” would have “materially modified [his] opinion regarding mitigating circumstances.” After the California Supreme Court again denied Pinholster’s habeas petition, he appeared ready to proceed to federal court with Dr. Stalberg as his expert.
On June 5, 2001, Dr. Stalberg executed a more detailed declaration in which he stated that the penalty phase testimony of Mrs. Brashear was “profoundly misleading” as she failed to truthfully describe Pinholster’s early childhood, which “was marked by significant deprivation, physical abuse, and extreme neglect.” Dr. Stalberg again acknowledged that Pinholster likely suffers from a seizure disorder, and went on to opine that some of the violent incidents in Pinholster’s past — the breaking of his wife’s jaw and his assault on Officer Kaufman — could have been attributed to his seizure disorder.
After Dr. Stalberg refused, despite all of the new mitigating evidence, to alter his diagnosis of Antisocial Personality Disorder, Pinholster’s habeas counsel informed him that he would no longer be serving as their expert. Instead, in support of his amended federal habeas petition, Pinhol-ster choose to rely on the new expert testimony of Dr. Vinogradov and Dr. Olson. Dr. Olson concluded that “it is reasonably probable that Mr. Pinholster has suffered from partial epilepsy since at least 1968.” In support of his conclusion, Dr. Olson relied on the two head injuries Pinholster suffered as a child, Pinholster’s abnormal EEG at age nine,27 the descriptions of Pinholster’s seizures provided by other witnesses, and Pinholster’s treatment for seizures with standard anti-seizure medication.
Dr. Vinogradov relied on the same evidence as the other experts and conducted two face-to-face interviews with Pinholster. She implicitly rejected' Dr. Woods’s diagnosis, stating there was “no clear information supporting true full-blown hypomanic or depressive episodes.” However, she diagnosed Pinholster with “personality change, aggressive type, due to serious childhood head trauma.” She opined that, “[o]n the night of the crimes, while intoxicated on multiple substances, Mr. Pinhol-ster experienced perceptual aberrations and possible psychotic symptoms.”
The dissent believes that Pinholster has presented evidence of “substantial neurological and emotional disorders.” Dissent at 782. However, the only constant with *770regard to the evolving defense expert testimony has been Dr. Stalberg’s diagnosis of Antisocial Personality Disorder and the experts’ agreement that it is reasonably probable that Pinholster suffered from epilepsy.28 The California Supreme Court has faced a revolving door of experts, each presenting his or her own theory on Pin-holster’s mental health. Although we have no pronounced reason to question the credibility of Pinholster’s new experts, we conclude that no newly-minted expert theory to explain his behavior would have made a difference in the face of what Pinholster said and did.
Though the Supreme Court has recently highlighted defense counsel’s constitutional duty to adequately investigate mitigating evidence, we cannot say from the record either before the state or federal district court that it was objectively unreasonable for the California Supreme Court to deny relief. While trial counsel could have presented more detailed mitigating evidence — in the form of Pinholster’s social history and mental health history — that evidence falls short when compared to the mitigating evidence available in Williams, Wiggins, and Rompilla, and the overwhelming evidence in aggravation which Pinholster faced.
In Williams, had counsel performed effectively the jury would have learned that Williams’s parents were imprisoned for criminal neglect; Williams’s father repeatedly beat him; Williams was borderline mentally retarded and had not advanced beyond sixth grade; and, while in prison, Williams helped crack a prison drug ring, he returned a prison guard’s missing wallet, and prison officials testified that he was the least likely to act violently out of all the inmates. 529 U.S. at 395-96, 120 S.Ct. 1495. As the Supreme Court emphasized, this mitigating evidence coupled with the evidence the jury did hear— that “Williams turned himself in, alerting police to a crime they otherwise would never have discovered, express[ed] remorse for his actions, and cooperated] with the police after that” — could have influenced the jury’s view of Williams’s moral culpability. Id. at 398, 120 S.Ct. 1495. In Williams, the additional mitigating evidence tended to show that Williams’s “violent behavior was a compulsive reaction rather than a product of coldblooded premeditation.” Id. Pinholster, on the other hand, presented himself to the jury as a classic antisocial personality who revels in his disobedience to the law and social mores.
In Wiggins, defense counsel failed to present evidence that Wiggins’s mother was an alcoholic and abusive to Wiggins and his siblings, Wiggins entered foster care at age six, two foster mothers physically abused him, his second foster father repeatedly raped and molested him, he spent time homeless, and he was mentally *771retarded. 539 U.S. at 525, 535, 545, 123 S.Ct. 2527. In finding that Wiggins was prejudiced by his counsel’s ineffective assistance at the penalty phase, the Supreme Court compared Wiggins to Williams, noting that ‘Wiggins does not have a record of violent conduct that could have been introduced by the State to offset this powerful mitigating narrative.” Id. at 537, 123 S.Ct. 2527. Pinholster, in contrast, is the epitome of a repeat offender who specializes in violent crimes.
In Rompilla, had defense counsel conducted a sufficient investigation into mitigating evidence, the jury would have learned that Rompilla’s parents suffered from severe alcoholism; Rompilla’s mother drank during her pregnancy, causing Rom-pilla to develop fetal alcohol syndrom; Rompilla and his brothers also developed serious drinking problems; Rompilla’s father severely beat both Rompilla and his mother; Rompilla’s mother and father fought violently, with one incident resulting in his mother stabbing his father; and that Rompilla suffered a depraved childhood, during which he was locked in a mesh dog pen, isolated from other children, and slept in an attic with no heat. 545 U.S. at 391-92, 125 S.Ct. 2456. In addition, counsel would have found evidence suggesting that Rompilla suffered from schizophrenia and other mental disorders.
In contrast to the petitioner in Wiggins, who had no prior convictions nor a record of violent conduct, cf. Wiggins, 539 U.S. at 537, 123 S.Ct. 2527, Pinholster’s violent past — a past Pinholster proudly boasted about to the jury — offsets the mitigating evidence. Pinholster bragged that he had committed hundreds of armed robberies within a three-year time period. In addition, he admitted to a prior kidnaping, during which he held a knife to the victim’s throat. And, unlike the petitioner in Williams, Pinholster neither expressed remorse over the murders of Thomas Johnson and Robert Beckett, nor attempted to aid the police in their investigation. Rather, Pinholster threatened to kill the State’s lead witness, Art Corona, and proudly recounted his recusant behavior in front of the jury.29
*772We recognize that, at first glance, Pin-holster’s habeas petition more closely resembles that of the petitioner in Rompilla. Nevertheless, there are significant differences, and we must analyze an attorney’s alleged ineffective assistance of counsel on a case-by-case approach. See Rompilla, 545 U.S. at 393-94, 396, 125 S.Ct. 2456 (O’Connor, J., concurring). California law provides that, in determining the penalty, the jury shall consider, if relevant, “[t]he circumstances of the crime of which the defendant was convicted in the present proceeding and the existence of any special circumstances.” Cal.Penal Code § 190.3(a). Indeed, the trial court instructed the jury that “[i]n determining which penalty is to be imposed on the Defendant, you shall consider all of the evidence which has been received during any part of the trial of this case.” Here, the jury witnessed first-hand Pinholster’s lack of remorse. Cf. Schriro v. Landrigan,—U.S. -, 127 S.Ct. 1933, 1944, 167 L.Ed.2d 836 (2007) (noting that the “postconviction court was well acquainted with Landrigan’s exceedingly violent past and had seen first hand his belligerent behavior”); see also id. (“In his comments [to the sentencing judge], defendant not only failed to show remorse or offer mitigating evidence, but he flaunted his me-nancing behavior.” (internal quotation marks and first alteration omitted)). Justice Mosk specifically emphasized that point in authoring the decision for the California Supreme Court: “[Pinholster] himself made his criminal disposition clear [to the jury.] In fact, he gloried in it.” Pinholster, 4 Cal.Rptr.2d 765, 824 P.2d at 611.
Pinholster viciously beat the two murder victims, repeatedly stabbed them with a knife, and took their wallets for a gain of $23 and a quarter-ounce of marijuana.30 Yet, under oath, Pinholster denied murdering the victims and bragged about the successful hundred-plus robberies he had previously committed. Pinholster called himself a “professional robber,” and testified that he often wrote his name and scratched swastikas on other people’s property as a “sideline to robbery.”31 *773Moreover, the jury heard evidence that Pinholster was previously convicted for kidnaping, that he threatened to kill the State’s lead witness, and that, in a jealous rage, Pinholster slashed the arm of Thomas Mesquita with a straight razor.
Pinholster’s detailed account of his version of the events on the night of the murders would obviously affect the jury’s view of Pinholster’s mental impairment evidence. And, the jury also observed firsthand on the witness stand an individual who failed to respect the gravitas of the multiple murder trial through his unrepentant attitude. In addition to taking pride in his criminal background, Pinholster was openly disrespectful of the deputy prosecutor and ignored the seriousness of his underlying murders. The record reflects that Pinholster was either laughing or smirking during numerous stages of the deputy prosecutor’s cross-examination.
We cannot ignore the fact that, even while hearing Pinholster’s defense in the guilt phase of the trial, the jury was considering facts that were also relevant to appropriate punishment. See CaLPenal Code § 190.3(a). In his testimony, Pinhol-ster portrayed himself as a career criminal who reveled in his antisocial persona. As Dr. Rudnick explained in his declaration, “individuals with Antisocial Personality Disorder may have an inflated and arrogant self-appraisal, behave in a cocky or self-assured manner, lack realistic concern about their problems and display a glib, superficial charm.”32 The California Supreme Court, which acknowledged the fact that Pinholster “gloried” in his criminal history, could reasonably have concluded that no amount of clever “after-the-fact” assessment by habeas defense psychiatrists would have convinced even a single juror to change his vote.
V
We affirm the district court’s denial of Pinholster’s request for an evidentiary hearing on ineffective assistance of counsel at the guilt phase and remand for dismissal of the petition. We reverse the district court’s grant of habeas relief on his ineffective assistance of counsel claim at the penalty phase.
AFFIRMED in part, REVERSED in part, VACATED, and REMANDED.
. We extract many of the facts and procedural history from the California Supreme Court opinion affirming Pinholster's convictions and death sentence on direct appeal, Pinholster, 1 Cal.4th 865, 4 Cal.Rptr.2d 765, 824 P.2d 571, which are confirmed by our own independent review of the record.
. Kempf had a previous conviction for receiving stolen property and was under arrest when he first talked with the police. He told the jury that the authorities did not promise leniency or other benefits in return for his testimony. Pinholster, 4 Cal.Rptr.2d 765, 824 P.2d at 582.
. During rebuttal, the state called Eric Klem-etti who testified that he had purchased marijuana from Johnson at the Kumar residence at 9 p.m. He claimed that the house was not ransacked and everything was in order. Pin-holster, 4 Cal.Rptr.2d 765, 824 P.2d at 585.
. On rebuttal, Tapar contradicted Pinholster when she testified that Pinholster arrived at her house in Corona's car, not his own as he had said. She also claimed not to have known "Shotgun,” giving Pinholster no reason to discuss his death with her.
. Between April 20, 1982, and January 19, 1983, court-appointed counsel Marvin Part represented Pinholster. Attorney James Armstrong was appointed in his place in January 1983. Pinholster requested to proceed without counsel, and from March 17, 1983, to July 13, 1983, Pinholster represented himself. On July 12, 1983, the Los Angeles County Superi- or Court appointed Harry W. Brainard after Pinholster changed his mind. On December 20, 1983, the superior court also appointed Wilbur G. Dettmar as second counsel under California Penal Code section 1095. Brai-nard and Dettmar represented Pinholster during the guilt and penalty phases of his trial.
.On state habeas review, the Los Angeles County Superior Court held an evidentiary hearing and determined that Pinholster, while representing himself pre-trial, received actual notice of the State’s intent to seek the death penalty. Pinholster does not challenge that finding here.
. "Seizure disorder” is the medically preferred term for what is commonly known as epilepsy.
. The Diagnostic and Statistical Manual of Mental Disorders (DSM), DSM-III, the American Psychiatric Association's handbook in effect in 1984 for diagnosing mental disorders, describes Antisocial Personality Disorder as a *754personality disorder with a history of continuous and chronic antisocial behavior in which the rights of others are violated, persistence into adult life of a pattern of antisocial behavior that began before the age of 15, and failure to sustain good job performance over a period of several years. Lying, stealing, fighting, truancy, and resisting authority are typically prevalent in early childhood, and in adulthood these kinds of behavior continue and include the failure to accept social norms with respect to lawful behavior.
. At this time, the district court also granted the State’s motion for summary judgment on *755select claims, including Pinholster’s claims of ineffective assistance of counsel at the guilt phase discussed in section III of this opinion.
. The court may also grant a petition where the state court adjudication of a claim is based on an unreasonable determination of the facts in light of the evidence presented in the state court proceeding. 28 U.S.C. § 2254(d)(2). We will address § 2254(d)(2) only when applicable to Pinholster's appeal.
. The district court incorrectly concluded that the California Supreme Court’s decision disposing of Pinholster's penalty phase ineffective assistance of counsel claim was not an adjudication on the merits entitled to deference. The California Supreme Court’s denial of a habeas petition without comment or citation constitutes a decision on the merits of the federal claims. See Hunter v. Aispuro, 982 F.2d 344, 347-48 (9th Cir.1992); see also Gaston v. Palmer, 417 F.3d 1030, 1038 (9th Cir.2005). Though we would ordinarily look through the California Supreme Court’s summary denial to the "last reasoned decision[in the state court system],” Shackleford v. Hubbard, 234 F.3d 1072, 1079 n. 2 (9th Cir.2000), no other state court determination addresses ineffective assistance of counsel at the penalty phase. Absent a last-reasoned state court decision on this claim, we must "perform an ‘independent review of the record’ to ascertain whether the state court decision was objectively unreasonable.” Himes v. Thompson, 336 F.3d 848, 853 (9th Cir.2003) (quoting Delgado v. Lewis, 223 F.3d 976, 982 (9th Cir.2000)); see also Greene v. Lambert, 288 F.3d 1081, 1089 (9th Cir.2002).
. Pinholster requests that we take judicial notice of the following documents to support his assertion that the State unlawfully destroyed all of the physical evidence after trial: (1) an excerpt of the Master Index with a list of the State's physical evidence; (2) a certificate from the Los Angeles County Superior Court ordering the exhibits listed on the “non-valuable exhibit” list destroyed; and (3) the "non-valuable exhibit” list. We deny his request as these documents are not relevant to the resolution of this appeal. See Santa Monica Food Not Bombs v. City of Santa Monica, 450 F.3d 1022, 1025 n. 2 (9th Cir.2006).
. We are not holding, nor do we think the district court found, that Pinholster’s counsel’s statement that he "probably” would not have advised Pinholster to testify is sufficient to establish that counsel's failure to investigate was non-prejudicial. See Dissent Op. at 776 n. 2. Indeed, Pinholster uses counsel’s declaration to argue that he was prejudiced. Pinholster argues that had his trial counsel investigated the palm print he would have known there was a discrepancy and therefore never would have advised Pinholster to testify. Pinholster argues that without his testimony there was no evidence that he was in Kumar’s residence at the time of the murders and therefore counsel’s failure to investigate was prejudicial. As we discuss infra these arguments are simply unpersuasive as there was a wealth of other evidence proving Pin-holster’s presence in the Kumar residence.
. Contrary to the dissent's assertion, we are not saying that the existence of a "battle of the experts” reduces any prejudice resulting from counsel’s failure to investigate the palm print. See Dissent at 776 n. 2. We are simply saying that Collins's declaration creates only a battle of the experts; it does not prove Pinholster's contention that the State's expert was misinformed, improperly influenced, or lying.
. Brainard declared:
The strategy decided upon prior to trial was to demonstrate Scott committed robberies and not burglaries, and that Scott used guns, not knives, as weapons. I assumed Scott would admit to having committed a few robberies, not hundreds, although we never explicitly discussed the number. Part of [the] strategy decided upon prior to trial was to admit the Croutch robbery during trial.
.The dissent assumes that trial counsel never advised "Pinholster against testifying, because the jury would likely conclude he was lying.” See Dissent at 777. There is a dearth of evidence in the record detailing any discussion between trial counsel and Pinholster about his decision to testify during the guilt phase. Pinholster does not allege, and there is no evidence to support, the dissent’s assumption that trial counsel neglected to discuss the risks of testifying with their client.
. Trial counsel did not object to replaying the tape during deliberations, or allowing the jury to keep the transcript while deliberating.
. Unlike Pinholster’s other ineffective assistance of counsel claims, the California Supreme Court reached the merits of this claim in the direct appeal. It therefore constitutes the "last reasoned decision” of the state court. See Shackleford, 234 F.3d at 1079 n. 2.
. The colloquy during the change of plea hearing went as follows:
The court: Mr. Pinholster, Count I of the information charges that on August 21st of last year you kidnapped a person named Jena, J-e-n-a, Rae, R-a-e, Burdett, B-u-r-d-e-t-t; that is, that you forcefully took her from one place to another. Do you understand that charge? Pinholster: Yes, sir. The court: Is that what you did? Pinholster: Yes, sir.
. The Slate contends the district court abused its discretion by granting Pinholster a federal evidentiary hearing. The State argues that the district court failed to consider whether Pinholster — given his shifting medical impairment theories and new lay witness declarations — properly developed a factual basis for his claim in state court. See Baja v. Ducharme, 187 F.3d 1075, 1078 (9th Cir.1999). The State waived this issue by failing to raise it in its opening brief. See United Stales v. Kama, 394 F.3d 1236, 1238 (9th Cir.2005). Moreover, as we discuss infra, any error was harmless.
. Because the California Supreme Court summarily denied Pinholster's penalty phase ineffective assistance of counsel claim, we have independently reviewed the record to ascertain whether the state court decision was objectively unreasonable. See Himes, 336 *766F.3d at 853; Pirtle v. Morgan, 313 F.3d 1160, 1167 (9th Cir.2002). Though unable to analyze the basis for the state court’s decision, we still view the decision through the "objectively unreasonable” lens. See Delgado, 223 F.3d at 982.
. Despite Chief Judge Kozinski’s misgivings, Rompilla v. Beard, 545 U.S. 374, 125 S.Ct. 2456, 162 L.Ed.2d 360 (2005), does not signal a change in the Supreme Court’s approach to analyzing the prejudice prong under Strickland. See Kozinski Concurrence at 773-74. The Court's decision not to address the aggravating evidence in Rompilla more likely re-suited from its conclusion that petitioner was clearly prejudiced from his counsel’s ineffective assistance, see 545 U.S. at 390, 125 S.Ct. 2456 ("We think Rompilla has shown beyond any doubt that counsel’s lapse was prejudicial; Pennsylvania, indeed, does not even contest the claim of prejudice”), rather than from an express desire to overrule prior precedent.
. But even the dissent concedes that the aggravating evidence here is stronger than that in Wiggins because Wiggins, unlike Pin-holster, did not have a record of violent conduct. See Dissent at 786.
. The district court refused to consider statements made in Duvall's interview notes on the basis that the notes constituted inadmissible hearsay. However, the parties stipulated to the admission of these interview notes during the evidentiary hearing; Pinholster’s habeas counsel made no objection based on hearsay. See United States v. Foster, 111 F.2d 871, 877 (9th Cir.1983) (stating that, where there is no objection to hearsay evidence, "such evidence is to be given its natural probative effect as if it were in law admissible” (internal quotation marks omitted)). Furthermore, the Supreme Court has instructed us to " 'evaluate the totality of the evidence — both that adduced at trial, and the evidence adduced in the habeas proceeding[s].’ " Wiggins, 539 U.S. at 536, 123 S.Ct. 2527 (quoting Williams, 529 U.S. at 397-98, 120 S.Ct. 1495).
. The dissent questions our consideration of Pinholster's description of his social history. See Dissent at 781-82. We are not crediting Pinholster's description of the events over that of other family members. We recognize that Pinholster was likely beaten and abused by both his step-father and maternal grandmother. While we in no way condone such treatment of any child, our role in these inquiries is to try and assess the extent of the mitigating evidence as it relates to the potential prejudice to Pinholster. In doing so, Pin-holster’s own perception of his childhood and its affect on him is certainly relevant. We also find relevant the fact that Pinholster's paternal grandfather provided some stability during Pinholster’s early childhood.
. None of the other experts agreed with Dr. Woods's diagnosis of bipolar mood disorder. In his June 2001 declaration, Dr. Stalberg stated that Pinholster "was substantially impaired by a bipolar mood disorder operating synergistically with intoxication and a seizure disorder at the time the crime was committed.” However, during the evidentiary hearing, Dr. Stalberg rejected that statement as his own testimony. He stated, "I never said that and never testified to [Pinholster having bipolar mood disorder].” Subsequently, in *769August 2002, Dr. Stalberg filed another declaration in which he stated simply that Dr. Woods's diagnosis of bipolar mood disorder was "incorrect.” Dr. David Rudnick, a neu-ropsychiatrist who served as an expert for the State during the federal evidentiary hearing, stated in his declaration of July 11, 2001, that "[t]here is no evidence for the diagnosis of bipolar disorder at any time in Mr. Pinhol-ster’s life.” Similarly, Dr. Vinogradov stated that she found "no clear information supporting true full-blown hypomanic or depressive episodes.”
. Dr. Rudnick testified that Pinholster’s abnormal EEG in 1968 could have been caused by his Attention Deficient Hyperactivity Disorder, or by the fact that he was only nine-years-old at the time. As Dr. Rudnick described, maturation of the brain is "characterized by a reduction in slow wave activity of the same frequencies observed” in Pinholster.
. Dr. Rudnick agreed with Dr. Stalberg's diagnosis and also noted in his declaration that John Geiger, M.D., a staff psychiatrist at San Quentin State Prison, diagnosed Pinhol-ster with Antisocial Personality Disorder and concluded that his violent behavior was "approximately that of the average condemned area inmate.” Charles E. Steinke, Ph.D., a staff psychologist at San Quentin, also agreed with Dr. Geiger’s diagnosis of Anti-social Personality Disorder. We have previously noted that a diagnosis of Antisocial Personality Disorder is "potentially more harmful to [a] petitioner than [helpful].” Gerlaugh v. Stewart, 129 F.3d 1027, 1035 (9th Cir.1997); see also Daniels v. Woodford, 428 F.3d 1181, 1204-05 (9th Cir.2005) (concluding that the jury "never heard any mitigating psychological explanation for Daniels’s behavior” because trial counsel relied solely on testimony suggesting that Daniel was a "sociopath”); Claboume v. Lewis, 64 F.3d 1373, 1384 (9th Cir.1995) (stating that omitted mental health records were "hardly ... helpful” as they indicated that the defendant had "an antisocial personality”).
. During the penalty phase, the jury also heard evidence regarding the numerous threats and assaults Pinholster inflicted on law enforcement, as well as several disciplinary infractions while he was arrested and incarcerated. For example, LAPD officers Kaufman and Guzman testified that Pinhol-ster kicked or attempted to kick them in the head while they tried to restrain him on different occasions. Los Angeles County Central Jail Operations Sergeant Thomas Piggott testified to some of the eleven disciplinary incidents with Pinholster involving "overt violence or some challenge to future recalcitrant type behavior.” Finally, the State presented the testimony of Cathy Ann Smith. She testified that Pinholster broke her jaw while seemingly having an epileptic seizure. However, because trial counsel could have rebutted some of this aggravating evidence, we do not give it substantial weight in the reweighing of the aggravating and mitigating factors. For example, former Los Angeles County Deputy Sheriff Dale Peroutka would have testified that Pinholster "eventually [] turned himself around” such that Peroutka and other deputies recommended to reclassify Pin-holster from administrative segregation to the general population. Peroutka no longer saw Pinholster as a danger to other deputies or inmates; he reached an agreement with Pin-holster that he could join the general population if he behaved and complied with the rules. Likewise, trial counsel could have diminished the impact of a serious disciplinary infraction admitted by stipulation. Allan Page Crowder, the corrections officer Pinhol-ster allegedly threatened to throw off a tier in state prison, would have testified that had he been a more seasoned officer, he would not have considered the 1978 verbal altercation worthy of a CDC 115 disciplinary report. Nevertheless, because we find other more substantial aggravating evidence in the record, this newfound mitigating evidence does not change our ultimate conclusion that no *772reasonable juror would have been persuaded to change his vote.
. The dissent questions the heinousness of these murders, comparing this factual scenario with those found in Belmontes v. Brown, 414 F.3d 1094 (9th Cir.2005), rev’d on other grounds, Ayers v. Belmontes, 549 U.S. 7, 127 S.Ct. 469, 166 L.Ed.2d 334 (2006); Hovey v. Ayers, 458 F.3d 892 (9th Cir.2006); and Fields v. Brown, 431 F.3d 1186 (9th Cir.2005). Dissent at 4797-99. However, for the jury charged with the duty of weighing the mitigating and aggravating factors in determining whether this defendant should receive a life sentence or suffer death, these separate, unconnected murders are irrelevant. Unlike a trial judge who may try several murder cases, or an appellate court that may review several different murder convictions in those states imposing a proportionality review on appeal in capital cases, this is likely the first and only time these juty members will become so intimate with facts involving the taking of human lives. The jury does not compare one murder to another, ranking the heinousness of the individual crimes on some imaginary scale. California does not require a proportionality review as do some other states in death penalty cases. Rather, as the Supreme Court has directed appellate courts to do, juries also consider the underlying facts of a death penalty case on an individualized case-by-case basis in weighing the aggravating and mitigating facts. Cal.Penal Code § 190.3. We do not share our colleague’s view that this was not a particularly heinous double homicide.
. Dr. Rudnick stated that "[Pinholster's] behavior at Lisa Tapar's house was a clear, angry reaction to having the door closed on him. After stabbing the door, he performed the very deliberate, aggressive act of carving various Nazi symbols on Lisa’s car.” This analysis, along with Pinholster’s ability to give a detailed description of his actions during *773this event, would not have been forgotten by the jury considering any of the newly proffered mitigating evidence.
. As detailed above, Dr. Woods used Pinhol-ster's behavior at trial to support his diagnosis of bipolar mood disorder. Given that Pinholster chose not to rely on Dr. Woods's diagnosis in his federal habeas petition, and that both Dr. Stalberg and Dr. Rudnick discredit this diagnosis, we cannot believe the jury would have given it much weight.