Opinion by Judge GRABER; Partial Concurrence and Partial Dissent by Judge BERZON.
OPINION
GRABER, Circuit Judge:Petitioner Kevin Artice Miles appeals the district court’s denial of his habeas petition, brought pursuant to 28 U.S.C. § 2254. Petitioner challenges only his capital sentence; he does not challenge his underlying felony murder conviction, arising from his role in a car-jacking.1 Peti*1130tioner argues that his counsel was ineffective at sentencing because she failed to focus on Petitioner’s drug addiction (rather than on intoxication), enlisted an unqualified expert, and failed to investigate Petitioner’s social history thoroughly enough.
We have jurisdiction pursuant to 28 U.S.C. §§ 1291 and 2253, and we affirm.
FACTUAL AND PROCEDURAL HISTORY
A. The Crime
On an afternoon late in 1992, Petitioner was standing on a street corner in Tucson, Arizona, with Levi Jackson and Ray Hernandez. Jackson was carrying a pistol that the three of them had just obtained together; he had told Petitioner and Hernandez of his plan to commit a car-jacking. Specifically, according to Petitioner’s post-arrest statement to the police, Jackson had told them that he was “gonna get somebody’s car, take 'em off in the middle of the desert, and shoot 'em.” At the time, Jackson and Hernandez were both 16 years old. Petitioner was 24 years old.
When Patricia Baeuerlen drove up and stopped at the corner, Jackson approached her car and asked for “a light.” When she turned to reach her cigarette lighter, Jackson pointed the weapon at her and told her to move over. He unlocked the car to allow Petitioner and Hernandez to enter and sit in the rear. While Jackson drove the car out to the desert, Hernandez held the pistol, but Petitioner also held it at some point. They drove Baeuerlen out of the city, into the desert, and stopped at a dirt road. There, Jackson told Baeuerlen to get out of the car and take off her shoes and jacket. She obeyed. After taunting and harassing Baeuerlen for five to ten minutes, Jackson suddenly shot her in the chest. Baeuerlen died as a result of the gunshot. According to testimony presented at trial and sentencing, Jackson — not Petitioner — shot Baeuerlen as he and Petitioner were walking away from Baeuerlen and returning to the car. Throughout the ordeal, starting with the drive to the desert, Baeuerlen was pleading for her life.
After the shooting, Jackson, Petitioner, and Hernandez drove away. According to Petitioner’s post-arrest statement, he thought that Baeuerlen was still alive when they left her in the desert. No one sought help for Baeuerlen. Later the same day, Petitioner used Baeuerlen’s ATM card, and a PIN that he had found in her belongings, to take money out of her bank account. The next day, Petitioner drove Baeuerlen’s car to Phoenix, where he went shopping at malls, exchanged Baeuerlen’s children’s Christmas presents for other goods, and went drinking with old friends. Petitioner told those friends about the murder, insisting that he did not pull the trigger, but smiling and laughing as he related the events.
B. Arrest and Interrogation
In the early hours of the following morning, that is, the second day after the murder, police arrested Petitioner in Chandler, Arizona, following a high-speed chase in Baeuerlen’s car. The police found Baeuerlen’s ATM card, credit card, jewelry, and other personal items in his possession. Later that morning, Tucson detectives began a tape-recorded interrogation that lasted about five hours. During the interrogation, Petitioner initially explained his possession of the car by telling the detectives two different stories, neither of which placed him at the scene of the murder. *1131But, after several hours of interrogation, Petitioner admitted to his involvement in the murder. Specifically, he admitted to knowing of Jackson’s plan to car-jack and shoot someone, to participating in obtaining the pistol with Jackson and Hernandez, to holding the weapon at some point during the drive out to the desert, and to watching Jackson shoot Baeuerlen.
C. Trial and Sentencing
Soon after Petitioner’s arrest, Barbara Sattler was appointed as his counsel and represented him through trial and sentencing. After a jury convicted Petitioner of first-degree felony murder, dangerous kidnapping, and dangerous armed robbery,2 the trial court reviewed a pre-sentence report (“PSR”) and held a sentencing hearing.
The PSR states that the crime occurred at around 1:30 p.m. and that Petitioner reported having used crack cocaine “four or five hours earlier” and not having slept the night before. The PSR also contains statements from Petitioner that he expected to get money from the car-jacking and that he wanted to commit another robbery with the pistol. The PSR repeats Petitioner’s assertions that he did not believe that Jackson would kill Baeuerlen and that Petitioner thought that Jackson would have killed him if he had tried to stop the murder.
The social history section of the PSR contains the following information. Petitioner was adopted at the age of 4 months. His adoptive mother was an alcoholic who nevertheless maintained employment, eventually rising past jobs as a waitress and cook to become a nursing home administrator. Although Petitioner is black, his adoptive mother was white, which caused some degree of social problems; those problems grew worse when Petitioner and his mother moved to a more affluent neighborhood. Petitioner found a way to fit in by becoming a “class clown” and by playing basketball. Indeed, despite poor grades, he graduated from high school and won a basketball scholarship to a Bible college, but he dropped out of college after only a week. Petitioner later served in the Navy, where he was disciplined for substance abuse and assault before receiving an other-than-honorable discharge. He also married and had a child, though he later grew apart from his wife and began using drugs. His wife eventually left him, leading him to be evicted from their apartment. A month later, his mother died, and his drug habit grew worse.
At the sentencing hearing, Sattler called an expert, Dr. Martin Levy, Ph.D., to discuss Petitioner’s drug use. Dr. Levy is a clinical psychologist who had evaluated Petitioner during a two-hour session. Dr. Levy testified that Petitioner reported using crack cocaine the night before the carjacking. In particular, Dr. Levy testified that Petitioner’s “mental state was compromised by intoxication ... with cocaine.” (Emphasis added.) Dr. Levy also testified that Petitioner’s description of his mental state during the crime suggested a state of “disassociatfion],”3 which was consistent with Petitioner’s reported drug use.
The prosecutor objected to Dr. Levy’s testimony on the ground that it lacked foundation. The sentencing judge agreed and determined that, because Dr. Levy *1132had insufficient knowledge of when and in what quantities Petitioner used drugs, he could not testify with specificity as to Petitioner’s level of impairment or judgment at the time of the crime. Nevertheless, in Sattler’s closing argument, she reiterated her position that Petitioner was “under the influence of drugs and alcohol that day.”
Sattler focused only briefly on Petitioner’s social history at sentencing. Two character witnesses testified about his background and his nonviolent nature.4 Indeed, Sattler’s closing arguments characterize him as a relatively normal person — one who graduated from high school, who usually maintained gainful employment, who served in the military and completed most of his term of service, who married, and who had a child — but who made some mistakes after his wife left and his mother died.
Ultimately, the trial judge sentenced Petitioner to death by lethal injection.5 In so doing, the trial judge cited three aggravating factors:6 (1) that Petitioner had previous convictions for three separate crimes of violence (armed robberies), (2) that Petitioner committed the carjacking in pursuit of pecuniary gain, and (3) that the murder was committed in an especially cruel manner.7 The trial court also noted that the murder was senseless, in that it was unnecessary to the escape of Petitioner and his accomplices.
In mitigation, the trial judge rejected most of the potential mitigating factors. He rejected the contention that Petitioner was only a minor participant in the crime. The trial judge also rejected unforeseeability 8 of the murder and Petitioner’s age as mitigating factors. As to expressions of remorse, the trial judge found them insincere and, in any event, outweighed by the aggravating factors listed above:
The court finds that the defendant’s expression of remorse was insufficient to outweigh the aggravating circumstances of this case. No remorse was evidenced when the defendant went to Phoenix, after the murder, in the car of Miss Baeuerlen, to party with his friends. No remorse was evidenced when the defendant was captured by the Phoenix Police. No remorse was evidenced when the defendant, a day after the murder, was able [to] laugh when detailing the murder ... to a boyhood friend in Phoenix.
*1133The trial judge rejected the possibility of rehabilitation, finding no evidence to support it. He went on to note that, even if he were to find a possibility of rehabilitation, that would not outweigh the aggravating factors. The trial judge also found that Petitioner’s cooperation with the police was purely self-interested and not sufficient “to establish a mitigating circumstance or to outweigh the aggravating circumstances.”
The trial judge did consider mitigation arising from the nature of the murder conviction — felony murder, rather than pre-meditated murder — but found it insufficient to outweigh the aggravating factors. The trial judge also considered Petitioner’s reputation for nonviolence but did not find it sufficient to outweigh the aggravating factors, especially in view of Petitioner’s recent commission of three armed robberies.
Finally, of particular significance to this appeal, the trial judge rejected any drug-related mitigation, stating:
The court finds that there is no credible evidence that the defendant’s capacity was impaired or that drugs or alcohol had impaired the defendant’s thinking or actions at the time of the crimes in question.... The testimony offered by the defendant, from Doctor Levy, Ph.D., as to impairment, was without adequate foundation, and considered by the court to be without value.
D. Post-Conviction Relief Proceedings
On direct appeal, the Arizona Supreme Court affirmed the conviction and capital sentence. State v. Miles, 186 Ariz. 10, 918 P.2d 1028 (1996). Petitioner did not petition for certiorari to the United States Supreme Court, but he did file a state court petition for post-conviction relief (“PCR”) under Rule 32 of the Arizona Rules of Criminal Procedure. The Arizona Superior Court denied Petitioner’s PCR petition, rejecting his ineffective assistance of counsel claims on the merits. With respect to Sattler’s failure to focus on addiction, the state court concluded both that Sattler’s performance was not deficient and that Petitioner failed to demonstrate prejudice. With respect to the other two claims in this case, the state court concluded only that Sattler’s performance was not deficient — it made no determination as to prejudice. The Arizona Supreme Court denied the petition for review of the PCR decision.
Before denying Petitioner’s PCR petition, the Arizona Superior Court, however, ordered an evidentiary hearing. In preparation for that hearing, Petitioner underwent more extensive psychological testing. Dr. Joseph Geffen, Ph.D., a clinical psychologist, prepared a report describing Petitioner as using drugs to “self-medicat[e]” and as having resorted to crime because of “his perceived need for drugs without which he cannot cope.” Dr. Levy had described Petitioner’s drug use similarly, as self-medication, in his pre-sentence evaluation, but did not connect Petitioner’s motivation for his crimes to a need to acquire drugs.
In preparation for the state hearing, Petitioner’s counsel hired an investigator to probe further into his social history. The investigator produced a detailed report, containing information gleaned from interviews with many people who knew Petitioner and his mother during his youth. The additional history confirms that Petitioner’s mother was an alcoholic and suggests that she may also have used heroin, or at least socialized with those who did. The investigation revealed that his mother worked as a prostitute and perhaps ran her own whorehouse out of her home. When Petitioner was approximately 11 years old, his mother began work at a nursing home (and may have given up prostitution); there, she rose to *1134become an administrator, a position she held until Petitioner’s last year of high school, when she was fired for drinking on the job. Additionally, the report characterized Petitioner’s hometown of Winslow, Arizona, as being segregated, corrupt, and rife with prostitution, crime, drugs, and gambling. The investigation confirmed that Petitioner and his mother suffered at least some alienation due to their mixed-race household.
The additional social history also suggests that Petitioner’s mother was an “extremely protective mother” who made him the center of her life. She was “infatuated” with her son and “coddle[dj” him. She slept in the same bed as Petitioner until he was 14 years old. She “read to him constantly and sang to him when she fed him,” past an age considered “normal” by a friend. The additional social history reveals that, although Petitioner’s mother disciplined him by spanking him with a hairbrush when he was 4 or 5 years old, she later discontinued the practice and did not physically abuse him.9 She bought Petitioner “everything he wanted” and, when he developed buck teeth, for which other children teased him, she arranged for him to get braces.
The additional social history report went on to discuss Petitioner’s relationships with his community. He went to church twice a week for Bible study until at least his junior high school years, receiving a ride from a local bus ministry. When he was in junior high school, his basketball coach frequently drove him home from practices. He became good friends with a local family, spending a great deal of time at their home; indeed, they treated him like their own child. Notably, he remained in contact with members of that family well into adulthood — two of them were character witnesses at his sentencing hearing. According to those two witnesses, Petitioner stayed in touch with them after leaving Winslow and visited them to introduce his wife. One of the witnesses was a close friend when she and Petitioner were both living in Tucson; she was present for the birth of his daughter.
The additional social history investigation also looked into Petitioner’s high school years, during which he played on the basketball team and earned a varsity letter in his senior year, helping to win the state championship. He had a close-knit group of five friends, and he was popular with girls.
E. Federal Habeas Proceedings
In late 2001, Petitioner filed this habeas corpus petition pursuant to 28 U.S.C. § 2254. The district court granted Petitioner’s request for appointment of an investigator and a doctor, and the court later granted requests for more funds for mitigation specialists.
Under the district court’s order, Dr. Geffen, who had examined Petitioner during the state post-conviction proceedings, examined him again and prepared another report. In his report, Dr. Geffen stated that, after learning about “modern methods of evaluating mitigation factors in death penalty cases,” years after his initial evaluation of Petitioner, he thought that he “had not done as complete an evaluation as possible.” Dr. Geffen further concluded: *1135(1) that Petitioner was “experiencing an altered state of mind at the time of [Baeuerlen’s] murder;” (2) that, “[although physically present, [Petitioner] was emotionally and mentally ‘not there’ in terms of his awareness and appreciation of events around him, due to a dissociative state of mind, during which the event appeared to him as unreal and disconnected from him;” (3) that Petitioner’s “substance abuse at the time was part of a lifelong adjustment problem which resulted in a severe state of depression, and that the drugs served the purpose of numbing his perceptions after some catastrophic losses and personal failures, including the loss of his mother and of his marriage and family and job, almost simultaneously, rather than being an isolated recreational act;” and (4) that Petitioner’s “altered mental state met the criteria for statutory mitigation, since he was not capable of conforming to the lawful requirements due to his impaired mental state.”
Around the same time, Petitioner was also examined by Dr. Wm. Michael Cochran, M.D. Dr. Cochran concluded that, “at the time of his participation in the crime(s) on December 7, 1992, [Petitioner] was using alcohol, crack cocaine and marijuana addictively” and that Petitioner’s “participation in the robbery of [ ] Baeuerlen was primarily motivated by his addictions, and their consequent monetary obligations to satisfy the attendant ‘needs’ for continued use.”10
In 2004, the district court granted, in part, Petitioner’s motion for an evidentiary hearing by allowing depositions of Sattler and Phyllis Howell (Sattler’s trial investigator). But the district court ultimately determined that an evidentiary hearing was “neither warranted nor required because Petitioner ha[d] not alleged facts which, if proved, would entitle him to relief.” The district court then denied Petitioner’s petition, certifying only the issues discussed in this opinion. Petitioner timely appealed, and we have jurisdiction pursuant to 28 U.S.C. § 2253. After oral argument and submission of the case, the Supreme Court issued its decision in Martinez v. Ryan, — U.S. -, 132 S.Ct. 1309, 182 L.Ed.2d 272 (2012), and we ordered supplemental briefing to address the effect, if any, of Martinez on the certified issues in this case.
STANDARDS OF REVIEW
We review de novo a district court’s denial of habeas corpus relief. Robinson v. Ignacio, 360 F.3d 1044, 1055 (9th Cir. 2004).
Our review of the underlying state court decisions, on the other hand, is more limited. Because Petitioner filed his § 2254 habeas petition after April 24, 1996, his petition is governed by the Antiterrorism and Effective Death Penalty Act of 1996 (“AEDPA”), Pub.L. No. 104-132, 110 Stat. 1214. Lambert v. Blodgett, 393 F.3d 943, 965 (9th Cir.2004). Under AEDPA, we must defer to a state court’s decision with respect to any claim that was adjudicated on the merits unless the adjudication of the claim:
(1) resulted in a decision that was contrary to, or involved an unreasonable application of, clearly established Federal law, as determined by the Supreme Court of the United States; or
(2) resulted in a decision that was based on an unreasonable determination of the facts in light of the evidence presented in the State court proceeding.
28 U.S.C. § 2254(d).
Under § 2254(d)(1), a state court’s decision involves an “unreasonable application” *1136of clearly established federal law if it “identifies the correct governing legal principle from [the Supreme Court’s] decisions but unreasonably applies that principle to the facts of the prisoner’s case.” Holland v. Jackson, 542 U.S. 649, 652, 124 S.Ct. 2736, 159 L.Ed.2d 683 (2004) (per curiam) (internal quotation marks omitted).
DISCUSSION
When applying AEDPA’s standards, we review the “last reasoned decision” by a state court addressing the issue at hand. Robinson, 360 F.3d at 1055 (internal quotation marks omitted). Here, the last reasoned opinion addressing the claims presently before us — whether counsel performed ineffectively at sentencing— is the Arizona Superior Court’s Minute Entry, which denied Petitioner’s PCR petition.
Clearly established Supreme Court precedent provides a framework for examining Sixth Amendment ineffective assistance of counsel claims. See Strickland v. Washington, 466 U.S. 668, 104 S.Ct. 2052, 80 L.Ed.2d 674 (1984). To establish ineffective assistance of counsel under Strickland, a prisoner must demonstrate both: (1) that counsel’s performance was deficient, and (2) that the deficient performance prejudiced his defense. Id. at 688-93, 104 S.Ct. 2052. We may address these prongs in whichever order we deem most efficient. Id. at 697, 104 S.Ct. 2052.
The first prong of the Strickland — test—deficient performance — requires a showing that counsel’s performance “fell below an objective standard of reasonableness,” id. at 688, 104 S.Ct. 2052, or was “outside the wide range of professionally competent assistance,” id. at 690, 104 S.Ct. 2052. The test is “highly deferential,” evaluating the challenged conduct from counsel’s perspective at the time in issue. Id. at 689, 104 S.Ct. 2052. This inquiry should “begin with the premise that ‘under the circumstances, the challenged action[s] might be considered sound trial strategy.’ ” Cullen v. Pinholster, - U.S. -, 131 S.Ct. 1388, 1404, 179 L.Ed.2d 557 (2011) (alteration in original) (quoting Strickland, 466 U.S. at 689, 104 S.Ct. 2052), rev’g Pinholster v. Ayers, 590 F.3d 651 (9th Cir.2009) (en banc). Under this objective approach, we are required “to affirmatively entertain” the range of possible reasons counsel might have proceeded as he or she did. Id. at 1407.
The second prong of the Strickland test — prejudice—requires the petitioner to demonstrate a “reasonable probability that, but for counsel’s unprofessional errors, the result of the [trial] would have been different.” 466 U.S. at 694, 104 S.Ct. 2052. “A reasonable probability is a probability sufficient to undermine confidence in the outcome.” Id. Further, as with any claim of constitutional error in a federal habeas case applied to state prisoners, an additional, essentially overlapping, harmless error standard applies: “whether the constitutional error ‘had substantial and injurious effect or influence in determining the [outcome].’ ” Ybarra v. McDaniel, 656 F.3d 984, 995 (9th Cir.2011) (quoting Brecht v. Abrahamson, 507 U.S. 619, 637, 113 S.Ct. 1710, 123 L.Ed.2d 353 (1993)), cert. denied, 81 U.S.L.W. 3195 (U.S. Oct. 9, 2012) (No. 11-10652).
The state court applied Strickland — the correct rule — in analyzing Petitioner’s claims.11 On habeas review, Petitioner’s *1137claims amount to a contention that the state court misapplied Strickland, so those claims fall squarely under § 2254(d)(1). See Knowles v. Mirzayance, 556 U.S. 111, 129 S.Ct. 1411, 1414-15, 173 L.Ed.2d 251 (2009) (evaluating an ineffective assistance of counsel claim under § 2254(d)(1)); Cheney v. Washington, 614 F.3d 987, 990 (9th Cir.2010) (same).
Our review of an ineffective assistance of counsel claim under § 2254(d)(1) and Strickland is “doubly deferential.” Knowles, 129 S.Ct. at 1420. The issue “is not whether [we] believe[ ] the state court’s determination under the Strickland standard was incorrect but whether that determination was unreasonable — a substantially higher threshold.” Id. (internal quotation marks omitted).
With that framework in mind, we evaluate Petitioner’s claims.
A. Addiction as a Mitigating Factor
Petitioner first argues that, during sentencing, Sattler unreasonably failed to focus on his drug addiction. We disagree. Sattler’s decision to rely on Dr. Levy and to focus on other mitigating factors, such as depression, rather than on addiction, was a matter of strategy.12 Sattler’s arguments at sentencing support our conclusion. Her chosen tack — characterizing Petitioner as a relatively normal person who was suffering from depression — evinces a desire to avoid painting Petitioner as a drug addict. At the very least, Sattler’s argument at sentencing raises the possibility that she was motivated by such a strategy, which is all that Pinholster requires. 131 S.Ct. at 1404-07. Because Sattler’s decision not to focus on drug addiction appears to have been motivated by reasonable strategic concerns, that decision is deserving of great deference under Strickland and Pinholster. See Turner v. Calderon, 281 F.3d 851, 876 (9th Cir.2002) (“The choice of what type of expert to use is one of trial strategy and deserves ‘a heavy measure of deference.’ ” (quoting Strickland’s statement regarding deference due to counsel’s investigative decisions, 466 U.S. at 691, 104 S.Ct. 2052)).
Petitioner also argues that Sattler’s representation was deficient because her sentencing arguments discussed intoxication rather than addiction. Sattler’s decision to avoid asserting that Petitioner suffered from an addiction, while focusing instead on lingering intoxication from the use of crack cocaine, could be seen as inconsistent with a strategy of painting Petitioner as a normal person; if counsel thought that drug use made Petitioner appear less deserving of sympathy, one might think that she would have tried to avoid mentioning drugs at all. But counsel’s strategy and decision are reasonable when viewed from her perspective at the time of trial, as Strickland requires us to do. Petitioner discussed his crack cocaine use in his confession, and it was mentioned in the PSR, so Sattler had to address it somehow.
Moreover, Petitioner was sentenced in 1993. As recently as 1998, the Arizona Supreme Court was routinely rejecting addiction as a mitigating factor unless the defendant could show intoxication at the time of the crime. See, e.g., State v. Greene, 192 Ariz. 431, 967 P.2d 106, 117 *1138(1998) (“To hold that a motivation to kill fueled in part by a desire for drugs is mitigating would be anomalous indeed.”); State v. Williams, 183 Ariz. 368, 904 P.2d 437, 453 (1995) (“Without a showing of some impairment at the time of the offense, drug use cannot be a mitigating circumstance of any kind.” (citing State v. White, 168 Ariz. 500, 815 P.2d 869, 882 (1991))); State v. Wood, 180 Ariz. 53, 881 P.2d 1158, 1176 (1994) (“We further believe Defendant’s impulsive personality and history of substance abuse merit little, if any, independent consideration in mitigation. As noted, Defendant was not under the influence of any intoxicating substance at the time of the murders.” (emphasis added) (citing State v. Bible, 175 Ariz. 549, 858 P.2d 1152, 1209 (1993))). But see State v. Gallegos, 178 Ariz. 1, 870 P.2d 1097, 1113-15 (1994) (finding error in trial court’s failure to consider history of substance abuse as a nonstatutory mitigating factor). For that reason, too, counsel would have had to emphasize intoxication.
It was only recently, in 2010, that we disapproved the Arizona Supreme Court’s treatment of addiction, in a habeas review of Williams, 904 P.2d 437. Williams v. Ryan, 623 F.3d 1258, 1270 (9th Cir.2010). Given the state of Arizona law at the time of trial, Sattler would have been operating under the assumption that intoxication was the only viable means of explaining Petitioner’s drug use to the sentencing judge. And the evidence did not rule out some sort of lingering intoxication — Dr. Levy discussed it in his report.13 Seen from this perspective, Sattler’s strategy did not fall outside the wide range of professional competence or below an objective standard of reasonableness.14
Even if Sattler had been deficient in failing to focus on addiction, we see no prejudice, the second prong of the Strickland standard. In assessing prejudice, we consider the mitigating effect of Petitioner’s drug addiction and how it would have altered the balancing of aggravating and mitigating factors discussed at sentencing. See Porter v. McCollum, 558 U.S. 30, 130 S.Ct. 447, 453-54, 175 L.Ed.2d 398 (2009) (per curiam) (“To assess th[e] probability [of a different sentence], we consider the totality of the available mitigation evidence — both that adduced at trial, and the evidence adduced in the habeas proceeding — and reweigh it against the evidence in aggravation.” (internal quotation marks omitted) (brackets omitted)).
As noted above, Petitioner’s case involved significant aggravating factors, none of which would be affected by addiction. For many of the proposed mitigating factors (remorse, rehabilitation, cooperation), the trial judge made two findings— (1) that the evidence was insufficient to establish the mitigating factor in the first place; and (2) that even if the mitigating factor were established, it would be insufficient to outweigh the aggravating factors. It is highly unlikely that a finding of addiction as a mitigating factor would have *1139tipped the scales where none of the other proposed mitigators did. Indeed, addiction could be characterized as merely another element of social history, which the sentencing judge considered and found insufficient to outweigh the aggravators. As stated by the district court:
The sentencing judge considered Petitioner’s life circumstances but found them insufficient to warrant leniency. There is no reasonable probability that focusing on Petitioner’s crack cocaine addiction, as opposed to the reasons that led to the addiction, would have changed the sentencing outcome.
Under AEDPA, the state court’s decision denying this portion of Petitioner’s ineffective assistance claim must stand. The state court did not apply Strickland unreasonably. See Harrington v. Richter, — U.S. -, 131 S.Ct. 770, 785, 178 L.Ed.2d 624 (2011) (“A state court must be granted a deference and latitude that are not in operation when the case involves review under the Strickland standard itself.”); cf. id. at 789 (“Rare are the situations in which the wide latitude counsel must have in making tactical decisions will be limited to any one technique or approach. It can be assumed that in some cases counsel would be deemed ineffective for failing to consult or rely on experts, but even that formulation is sufficiently general that state courts would have wide latitude in applying it.” (internal quotation marks omitted)).
“Surmounting Strickland’s high bar is never an easy task.” Id. at 788 (internal quotation marks omitted). Because Sattler’s decision not to focus on addiction as a mitigating factor was strategic and because Petitioner was not prejudiced as a result, he fails to meet the Strickland standard here.
B. Qualifications of Expert
Petitioner next argues that Sattler’s preparation of Dr. Levy was deficient. The sentencing court did not allow Dr. Levy to testify as to Petitioner’s drug use because of a lack of foundation — Dr. Levy did not know how often Petitioner had been using drugs, or in what quantities. He did not even know if, or for how long, Petitioner had slept between the time he ingested drugs and the time he committed the crime.
Although Sattler’s strategy — to focus on intoxication rather than addiction — was reasonable, she may have failed to implement it appropriately. But even if that failure represents performance so deficient as to meet the standards applicable when we review a Strickland claim under AED-PA — a question we do not decide — Petitioner still fails to demonstrate prejudice. On this point, the state court made no determination on the merits, so we must review de novo. See Porter, 130 S.Ct. at 452 (“Because the state court did not decide whether Porter’s counsel was deficient, we review this element of Porter’s Strickland claim de novo.”). Significantly, the sentencing judge was aware of Petitioner’s drug use — the PSR, which quoted some of Dr. Levy’s opinions, contained information about Petitioner’s “coming down” from crack cocaine used the night before the crime, as well as a diagnosis that ■ Petitioner was in a “disassociated” state. The excluded testimony would have added very little more.
Furthermore, as the district court noted, even if Dr. Levy could have testified as to the effect of Petitioner’s drug use on his mental state, that testimony would have been of limited value in view of: (1) Petitioner’s “acknowledgment that he was not under the influence of drugs or alcohol at the time of the offense”; and (2) Dr. Levy’s other testimony that “regardless of *1140his drug abuse Petitioner knew the difference between right and wrong and was capable of walking away from the offense, thus negating any finding of significant impairment under A.R.S. § 13-703(G)(1).”15 It is not reasonably probable that Dr. Levy’s excluded testimony would have influenced the sentencing judge because, even if the judge had considered Petitioner’s drug use to be a form of reduced, nonstatutory intoxication, the mitigating effect of that condition would have been insufficient to outweigh the aggravating factors outlined and discussed above. Consequently, Petitioner’s ineffective assistance of counsel claim, regarding the qualifications of Dr. Levy, fails on the prejudice prong of Strickland, reviewed de novo.
C. Investigation of Social History
Finally, Petitioner argues that Sattler’s performance was ’deficient because she failed to investigate mitigating circumstances thoroughly enough. Strickland itself involved a claim of ineffective assistance for failure to investigate mitigating circumstances. For that reason, Strickland is an especially good starting point for analyzing Petitioner’s claim that Sattler failed to investigate sufficiently his social history. The Supreme Court outlined the standards governing counsel’s duty to investigate as follows:
[Strategic choices made after thorough investigation of law and facts relevant to plausible options are virtually unchallengeable; and strategic choices made after less than complete investigation are reasonable precisely to the extent that reasonable professional judgments support the limitations on investigation. In other words, counsel has a duty to make reasonable investigations or to make a reasonable decision that makes particular investigations unnecessary. In any ineffectiveness case, a particular decision not to investigate must be directly assessed for reasonableness in all the circumstances, applying a heavy measure of deference to counsel’s judgments.
... And when a defendant has given counsel reason to believe that pursuing certain investigations would be fruitless or even harmful, counsel’s failure to pursue those investigations may not later be challenged as unreasonable.
Strickland, 466 U.S. at 690-91, 104 S.Ct. 2052 (emphasis added).
In Pinholster, the Supreme Court provided more guidance, overturning an opinion in which we had drawn, from other recent Supreme Court cases, a “constitutional duty to investigate, and the principle that it is prima facie ineffective assistance for counsel to abandon their investigation of the petitioner’s background after having acquired only rudimentary knowledge of his history from a narrow set of sources.” 131 S.Ct. at 1406 (citation, internal quotation marks, and brackets omitted). In the decision that Pinholster reversed, we had explained that we “could not ‘lightly disregard’ a failure to introduce evidence of ‘excruciating life history’ or ‘nightmarish childhood.’ ” Id. (quoting Pinholster, 590 F.3d at 684).
In reversing us, the Court in Pinholster explained Strickland:
“No particular set of detailed rules for counsel’s conduct can satisfactorily take account of the variety of circumstances faced by defense counsel or the range of legitimate decisions.... ” Strickland itself rejected the notion that the same investigation will be required in every case. It is “[r]are” that constitutionally *1141competent representation will require “any one technique or approach.”
Id. at 1406-07 (alteration in original) (citations omitted) (quoting Strickland, 466 U.S. at 688-89, 691, 104 S.Ct. 2052, and Richter, 131 S.Ct. at 788-89).
Here, Sattler’s actions are a reasonable implementation of her strategy — made explicit in her closing arguments at sentencing — to characterize Petitioner as a relatively normal person who made serious mistakes after his wife left and his mother died. Cf. Strickland, 466 U.S. at 672-74, 104 S.Ct. 2052 (finding that counsel’s strategy — claiming “no significant history of criminal activity” and arguing that the defendant “should be spared death ... because [he] was fundamentally a good person who had briefly gone badly wrong in extremely stressful circumstances” arising from “his inability to support his family”— was professionally reasonable, justifying a failure to investigate and present background information that might undermine those claims).
Sattler’s failure to investigate more thoroughly is justified, then, by the irrelevance of additional social history to her chosen strategy. As Pinholster recognized, choice of a particular strategy can make “particular investigations unnecessary.” 131 S.Ct. at 1407; see id. at 1407-OS (approving of the notion that “ ‘ “humanizing” the defendant ... may be the wrong tactic in some cases because experienced lawyers conclude that the [sentencing authority] simply won’t buy it’ ”) (quoting Pinholster, 590 F.3d at 692 (Kozinski, C.J., dissenting)).
Because Sattler’s actions reflect a deliberate choice of reasonable strategy, they do not fall outside reasonable professional norms. We see no deficient performance in Sattler’s decision not to investigate Petitioner’s social history further, and AED-PA deference applies. It is on this holding that we part ways with the dissent. The dissent rests on the premise that the Arizona Superior Court’s holding — that Sattler’s approach to mitigation was not deficient — was “contrary to” clearly established federal law and that, as a result, we should review Petitioner’s ineffective assistance of counsel claim de novo, not with AEDPA deference. That argument is flawed because it overreads Rompilla v. Beard, 545 U.S. 374, 125 S.Ct. 2456, 162 L.Ed.2d 360 (2005), and Wiggins v. Smith, 539 U.S. 510, 123 S.Ct. 2527, 156 L.Ed.2d 471 (2003), in contravention of Pinholster1 s clear instructions to the contrary. See 131 S.Ct. at 1406-07 (“The Court of Appeals erred in attributing strict rules to this Court’s recent case law.” (citing Rompilla and Wiggins)). Indeed, the dissent here appears to be making the same argument made by the dissent in Pinholster, an argument that was necessarily rejected by a majority of the Court. See id. at 1427 (Sotomayor, J., dissenting) (“In reaching this conclusion, the majority commits the same Strickland error that we corrected, applying § 2254(d)(1), in Wiggins: It holds a purportedly ‘tactical judgment’ to be reasonable without assessing ‘the adequacy of the investigation supporting [that] judgmenft].’” (alterations in original) (quoting Wiggins, 539 U.S. at 521, 123 S.Ct. 2527)).
Further, to the extent that the dissent finds support in Porter, 130 S.Ct. 447, that case is distinguishable. Porter held that the defendant “may have been fatalistic or uncooperative, but that [did] not obviate the need for defense counsel to conduct some sort of mitigation investigation.” Porter, 130 S.Ct. at 453. In Porter, counsel failed to conduct any investigation into the defendant’s background — he did not interview any witnesses or request any records. Id. Here, as the Arizona Superi- or Court held, Petitioner’s failure to disclose pertinent facts about his background “guaranteed that [Sattler] would not and Dr. Levy certainly would not, conduct fur*1142ther investigation into Petitioner’s background.” Sattler did conduct a mitigation investigation — she engaged an investigator who interviewed childhood friends of Petitioner, attempted to call his wife to testify at the penalty phase (but Petitioner refused to allow her to do so), and engaged Dr. Levy. Porter, therefore, is inapplicable here.
But even if Sattler’s performance had been deficient, Petitioner suffered no prejudice. As with Petitioner’s claim regarding Sattler’s expert, the state court made no prejudice finding on the failure to investigate claim, so we must review prejudice de novo. That review is not subject to the evidentiary limitations announced in Pin-holster, though it is subject to the limitations in § 2254(e)(2). See Pinholster, 131 S.Ct. at 1401 (“Section 2254(e)(2) continues to have force where § 2254(d)(1) does not bar federal habeas relief____ At a minimum, therefore, § 2254(e)(2) still restricts the discretion of federal habeas courts to consider new evidence when deciding claims that were not adjudicated on the merits in state court.”). But even assuming that § 2254(e)(2) permits us to consider the new evidence that Petitioner produced at the district court,16 we see no prejudice.
First, as discussed above, Petitioner received a capital sentence primarily on account of three aggravating factors — previous convictions for three armed robberies, committing the car-jacking in pursuit of pecuniary gain, and committing the murder in an especially cruel manner — and the sentencing judge observed that the aggravators were unlikely to be out-weighed by anything less than substantial mitigation. Petitioner’s additional social history is, as the district court noted, largely cumulative of what was already before the sentencing judge in the PSR, meaning that its mitigating value would be marginal.
More significantly, the additional social history is equivocal, and not as alarming as that of the defendants in other failure-to-investigate cases. See, e.g., James v. Ryan, 679 F.3d 780 (9th Cir.2012), petition for cert. filed, 81 U.S.L.W. 3047 (U.S. June 28, 2012) (No. 11A1119). Petitioner’s mother was a prostitute during his early years, though she turned to legitimate employment when he was about 11 years old. He may have observed — but did not experience — violence in connection with his mother’s prostitution. But, however problematic were the circumstances of Petitioner’s mother’s lifestyle, she did not neglect him, and there was no evidence that he was ever abused. To the contrary, Petitioner’s mother was clearly quite devoted to him. Moreover, whatever other problems existed in Petitioner’s hometown, he had a community of friends and a support system there, with responsible adults who took an interest in him. He developed healthy relationships that continued into adulthood. Finally, by all objective indications, he was socially well adjusted in high school.
Petitioner’s background was far more stable than, say, the background of the defendant in James, in which we granted habeas relief from a capital sentence.17 The defendant in that case, James, grew *1143up in a household with a father who shot heroin in front of James and was a violent alcoholic who beat James’ mother. James, 679 F.3d at 811. James grew up on welfare and was both neglected and verbally abused by his mother. Id. Later, his mother took up with another violent alcoholic, but this one abused James as well as his mother. Id. Growing up, James was frequently visited by an uncle known to have sexually abused other children in his family. Id. at 811-12. At one point, James’ mother tried to smother him with a pillow but relented at the last moment. Id. at 812. After living in various foster homes and an adoption center for six to nine months, James was given up for adoption at age 4. Id. He was eventually adopted by an older couple who physically abused him when he misbehaved.18 Id. at 812-13.
Similarly, the Arizona Supreme Court reversed a death sentence in State v. Trostle, 191 Ariz. 4, 951 P.2d 869 (1997). Unlike Petitioner here, Trostle had been neglected as a baby. Child Protective Services received numerous reports about him, starting with a report that he was found, at the age of 2 or 3 months old, sleeping in his own vomit while wearing a soiled diaper. Id. at 884. “His grandmother beat him regularly and once severely burned him with hot water for wetting his pants. His grandfather was convicted of sexually molesting him over a substantial period of time beginning at age 11.” Id. After Trostle began acting out in sexually inappropriate ways, juvenile authorities placed him in a residential treatment and educational program when he was 14 years old. Id.
The newly uncovered portion of Petitioner’s social history simply does not have significant mitigating value in view of what was already available to the sentencing judge. Thus, even if Sattler had been professionally deficient in failing to investigate and present these additional facts, it is not reasonably probable that the outcome of the aggravation/mitigation balancing would have been different. Indeed, the new evidence does little to dispel Petitioner’s later social history, in which he acted as a functioning member of society for a number of years, demonstrating a capacity to overcome the hardships that had burdened his youth.
Accordingly, the failure-to-investigate portion of Petitioner’s ineffective assistance claims fails on the first prong of Strickland, applying AEDPA deference. We note, however, that Petitioner’s claim would fail on the first prong even under de novo review. Further, as discussed above, even if Petitioner could prevail on the first prong, thereby requiring us to review de novo on the second prong, he would fail.19
*1144D. Effect 0/Martinez
Martinez does not help Petitioner. He had the assistance of counsel in his post-conviction relief proceeding, and counsel raised a claim of ineffective assistance of trial counsel. Assuming that Martinez applies in that situation, its exception is available only if Petitioner can establish that his postconviction counsel was ineffective under the Strickland standard and that the “underlying ineffeetive-assistanee-oftrial-counsel claim is a substantial one, which is to say that ... the claim has some merit.” 132 S.Ct. at 1318.
Here, it cannot be said that Petitioner’s postconviction counsel performed his duties so incompetently as to be outside the “wide range of professionally competent assistance.” Strickland, 466 U.S. at 690, 104 S.Ct. 2052. Even though Petitioner’s current counsel has now uncovered some new information beyond that presented to the state courts by his postconviction counsel, that evidence is insufficient to demonstrate that the previous lawyer’s investigation was objectively unreasonable. As detailed above, post-conviction counsel conducted an extensive investigation, obtaining a psychologist to perform further testing and hiring an investigator who visited Petitioner’s home town and interviewed many people who knew him and his mother. Accordingly, Petitioner cannot demonstrate that his post-conviction counsel was ineffective.
Furthermore, even with new evidence relating to his social history and drug use, Petitioner cannot rescue the claim that his sentencing counsel was ineffective. As we have already discussed, sentencing counsel made a reasonable choice, as a matter of strategy, not to focus on social history and addiction, opting instead to paint Petitioner as a normal person who made a grave mistake during a tumultuous period in his life. Petitioner’s new evidence does not establish that this choice was unreasonable.
In summary, even assuming that the Martinez exception applies to Petitioner’s case, he cannot satisfy its requirements.
CONCLUSION
Petitioner’s counsel adopted a permissible sentencing strategy to show: (1) that Petitioner was a nice young man who went with bad companions because he was depressed, who may have been intoxicated at the time of the crime, who was remorseful, and who was worth saving through rehabilitation; and (2) that he was just a very minor participant in the crime who was surprised by the violent turn of events. She presented mitigation witnesses to bolster this theory. To portray him as a crazed drug addict with a sordid past would have contradicted the chosen strategy. Petitioner’s arguments amount to little more than a contention that his counsel should have adopted a different strategy. Under Strickland, such arguments must fail, and Martinez does not compel a different result.
AFFIRMED.
. Petitioner briefed several additional issues that the district court declined to certify for appeal. Most of those issues relate to sentencing, but one challenges the conviction. We have examined all the uncertified issues, and none meets the standard for granting a certificate of appealability. See Miller-El v. Cockrell, 537 U.S. 322, 336, 123 S.Ct. 1029, 154 L.Ed.2d 931 (2003) (stating that a court should grant a certificate of appealability only *1130when a habeas petitioner has demonstrated "that reasonable jurists could debate whether (or, for that matter, agree that) the petition should have been resolved in a different manner or that the issues presented were adequate to deserve encouragement to proceed further” (internal quotation marks omitted)).
. As noted, none of these convictions is at issue here.
. Dr. Levy’s testimony and reports use the terms "disassociation” and "dissociation” interchangeably. "Dissociation” is a "[s]eparation of psychologic experiences and events that are normally related, leading to a distortion of experience and of the meaning of personal and interpersonal events.” Robert J. Campbell, M.D., Campbell’s Psychiatric Dictionary 289 (9th ed.'2009).
. In addition, Sattler planned to call Petitioner’s estranged wife to testify but did not do so because Petitioner had objected. Similarly, she planned to call two other character and background witnesses, but they were unavailable because of a medical emergency. At sentencing, Sattler made a statement on the record to document those circumstances.
. The conviction, sentencing, and appeal to the Arizona Supreme Court all took place before the Supreme Court decided Ring v. Arizona, 536 U.S. 584, 122 S.Ct. 2428, 153 L.Ed.2d 556 (2002), which requires a jury to determine all facts relating to eligibility for capital punishment. Ring "does not apply retroactively to cases already final on direct review.” Schriro v. Summerlin, 542 U.S. 348, 358, 124 S.Ct. 2519, 159 L.Ed.2d 442 (2004).
. The trial judge relied on an additional aggravating factor — that the murder was committed in an especially heinous manner — but the Arizona Supreme Court reversed on that point. See State v. Miles, 186 Ariz. 10, 918 P.2d 1028, 1035-36 (1996).
. To support the cruelty finding, the trial judge found that Baeuerlen "suffered prolonged mental anguish and uncertainty as to her fate,” as demonstrated by Petitioner's own account of her "crying, screaming in terror, and begging for her life.”
. The trial judge went on to note that Petitioner could not have been surprised by the killing in view of his accomplice's statement, before the crime, that he was "gonna get somebody’s car, take 'em off in the middle of the desert, and shoot 'em.”
. Petitioner now disputes this finding and recently filed an affidavit stating that his mother routinely physically abused him when he was between the ages of 4 and 14 years old by beating him with "belts, extension cords, paddles, switches, and her fists." Because this evidence was not before the state court, however, we may not consider it. See Cullen v. Pinholster, - U.S. -, 131 S.Ct. 1388, 1398, 179 L.Ed.2d 557 (2011) (holding that "review under [28 U.S.C.] § 2254(d)(1) is limited to the record that was before the state court that adjudicated the claim on the merits”).
. After Pinholster, the AEDPA standard of review prevents ns from relying on Dr. Cochran’s report or Dr. Geffen’s last report because the state court did not consider that evidence.
. The state court identified the Strickland legal standard without citing that particular case; rather, the state court cited only Arizona Supreme Court decisions. But those state court decisions, in turn, explicitly cite *1137and adopt Strickland. See State v. Vickers, 180 Ariz. 521, 885 P.2d 1086, 1090 (1994); State v. Nash, 143 Ariz. 392, 694 P.2d 222, 227 (1985).
. Sattler's deposition supports our conclusion, but after Pinholster, we may not consider that evidence under the AEDPA standard of review. 131 S.Ct. at 1400 ("[E]vidence introduced in federal court has no bearing on § 2254(d)(1) review.”). Accordingly, we do not rely on Sattler's deposition.
. Dr. Levy’s report discusses Petitioner’s condition at the time of the crime as “coming down” from crack cocaine use the previous night and notes that Petitioner was dissociated from the events. At trial, Dr. Levy testified that this state is common among drug users.
. To be sure, in Williams, we wrote: "The decision of the Arizona Supreme Court that drug use could not be considered as a mitigating factor ‘of any kind,' is contrary to the Supreme Court’s consistent decisions in capital cases beginning more than a decade before Williams’ [1992] trial." 623 F.3d at 1270 (emphasis added). Nevertheless, as Petitioner’s brief acknowledges, under Arizona law at the time of his trial, addiction was not a recognized form of mitigation. Thus, although she could have relied on existing United States Supreme Court decisions to challenge the Arizona practice of ignoring the mitigating value of addiction, her strategy merits deference under Strickland.
. Section 13-703 (1993) has since been renumbered as Arizona Revised Statutes section 13-751 (2011).
. Even under review de novo and § 2254(e)(2), however, we do not consider the new evidence produced on appeal in connection with the supplemental briefing on the Martinez issue discussed below. See United States v. Waters, 627 F.3d 345, 355 n. 3 (9th Cir.2010) ("Facts not presented to the district court are not part of the record on appeal.” (internal quotation marks omitted)).
. James is distinguishable on the deficiency-of-performance prong of Strickland because, in James, the state did not dispute deficient performance. 679 F.3d at 807. Also, the state court in James had denied the ineffective *1143assistance of counsel claim for procedural reasons, rather than on the merits, meaning that AEDPA deference did not apply. Id. at 802.
. The dissent asserts, "[C]ontrary to the majority's account, James did not ‘grow up’ in the abusive circumstances described. Instead, at age four, James was adopted by parents who were strict but loving, and his life circumstances from thence forward took a dramatic turn for the better.” Dissent at 1150. But James’ adoptive father was so "strict” that, "[o]n one occasion, [he] whipped James so severely with a rope that he raised bloody welts all over James’s back.” James, 679 F.3d at 813.
. Petitioner argues that the state court made an error of law in suggesting that it denied this portion of his ineffective assistance of counsel claims because his social history was not "new” evidence. Because Petitioner did not raise this argument in the district court, he may not raise it for the first time on appeal. See Scott v. Ross, 140 F.3d 1275, 1283 (9th Cir.1998) (identifying a general rule of waiver for issues not raised below, subject to a discretionary exception). Even if we allowed Petitioner to raise this argument, he could gain nothing more than review de novo *1144under the Strickland standard, which is itself deferential. See Frantz, 533 F.3d at 737 (holding that, when "§ 2254(d)(1) is satisfied, then federal habeas courts must review the substantive constitutionality of the state custody de novo”). As noted above, the failure to investigate portion of Petitioner’s ineffective assistance of counsel claims would fail even under review de novo.
. The state court also held that Miles could not make a claim under Arizona Rule of Criminal Procedure 32.1(e) because his evidence was not "new.” Postconviction Strickland claims in Arizona are brought under Rule 32.1(a), which allows post conviction relief when ‘‘[t]he conviction or sentence was in violation of the Constitution.” Because the two subsections provide separate grounds for relief, the state court’s discussion of Rule 32.1(e) does not bear on its Strickland analysis, and so it is irrelevant to this appeal.