Full Opinion

FOR PUBLICATION UNITED STATES COURT OF APPEALS FOR THE NINTH CIRCUIT ANDREW LAMONT BROWN, No. 21-99001 Petitioner-Appellant, D.C. No. 2:04- cv-03931-JVS v. RONALD BROOMFIELD, Acting OPINION Warden, San Quentin State Prison, Respondent-Appellee. Appeal from the United States District Court for the Central District of California James V. Selna, District Judge, Presiding Argued and Submitted September 10, 2025 San Francisco, California Filed August 14, 2026 Before: Richard R. Clifton, Jacqueline H. Nguyen, and Gabriel P. Sanchez, Circuit Judges. Opinion by Judge Sanchez 2 BROWN V. BROOMFIELD SUMMARY * Habeas Corpus / Death Penalty The panel affirmed the district court’s denial of Andrew Lamont Brown’s petition for a writ of habeas corpus under 28 U.S.C. § 2254 challenging his California conviction and death sentence for first-degree murder. The district court granted a certificate of appealability (COA) as to Brown’s claims that he received ineffective assistance of counsel during the penalty phase of his trial, that he was incompetent to stand trial, and that he has an intellectual disability that renders him ineligible for execution under the Eighth Amendment. Brown sought to expand the certificate of appealability to include three additional claims. The panel applied the deferential standard of review set forth in the Antiterrorism and Effective Death Penalty Act (AEDPA). Brown’s certified claim of ineffective assistance at the penalty phase contained numerous subclaims raising two general areas of concern: the failure to investigate and present important mitigation and evidence, and the failure to rebut uncharged acts introduced against Brown and to object to evidence and arguments raised by state prosecutors. • The panel held that the California Supreme Court could have reasonably determined that Brown failed to make a prima facie claim of ineffective assistance because there was no evidence that trial counsel * This summary constitutes no part of the opinion of the court. It has been prepared by court staff for the convenience of the reader. BROWN V. BROOMFIELD 3 failed to investigate or make reasonable strategic choices about Brown’s history of drug and alcohol abuse; mental health conditions; family history of abuse and neglect; gang ties; and poverty and neighborhood history. Much of the new evidence presented by Brown in his postconviction petitions was cumulative of the evidence trial counsel already presented at the penalty phase. Where trial counsel did not present or focus on certain evidence, the record reflects that these were strategic decisions by trial counsel. Therefore, the California Supreme Court could have reasonably concluded that trial counsel did not render deficient performance. In light of the doubly deferential standard of review under AEDPA, the panel could not conclude that the California Supreme Court’s rejection of Brown’s ineffective assistance claim was objectively unreasonable. • The panel held that in view of the trial record in which counsel presented several witnesses to refute the State’s evidence that Brown perpetrated the uncharged offenses, the California Supreme Court reasonably rejected Brown’s claims that trial counsel was ineffective for failing to call two individuals as rebuttal witnesses; and that counsel was not deficient in failing to present at the penalty phase certain of Brown’s positive qualities, in failing to request a jury instruction defining and clarifying life without parole, or in failing to object to or rebut the prosecutor’s argument at closing that Brown was a “sociopath” who lacked remorse and would kill again. 4 BROWN V. BROOMFIELD • Because counsel’s performance was not deficient, the panel did not address whether Brown was prejudiced by any deficiency. The panel held that based on the totality of the evidence, the California Supreme Court did not make an unreasonable factual determination that Brown failed to rebut the presumption that he was competent to stand trial. The panel held that the California Supreme Court reasonably determined that Brown failed to make a prima facie showing of intellectual disability under California’s statutory test. The panel declined to expand the COA to include three uncertified claims in which Brown alleged (1) counsel’s ineffective assistance at the guilt phase, (2) the discriminatory exclusion of a prospective black juror, and (3) the denial of a jury drawn from a fair cross-section of the community. COUNSEL Saivandana Peterson (argued), Nicole Jeong, and Susel B. Carrillo-Orellana, Deputy Federal Public Defenders; Cuauhtémoc Ortega, Federal Public Defender; Office of the Federal Public Defender, Los Angeles, California; for Petitioner-Appellant. Vincent P. LaPietra (argued) and Lise Jacobson, Deputy Attorneys General; Holly D. Wilkens, Supervising Deputy Attorney General; James W. Bilderback II, Senior Assistant Attorney General; Rob Bonta, California Attorney General; Office of the California Attorney General, San Diego, California; for Respondent-Appellee. BROWN V. BROOMFIELD 5 OPINION SANCHEZ, Circuit Judge: On March 5, 1992, Andrew Lamont Brown was sentenced to death after a California jury convicted him of first-degree murder and robbery and found true the special circumstance that he had killed Christina Ramirez while engaging in robbery and with the personal use of a firearm. After Brown was denied relief on direct appeal and in state post-conviction proceedings, he filed the instant petition for writ of habeas corpus under 28 U.S.C. § 2254. The district court denied his petition but granted a certificate of appealability as to Brown’s claims that he had received ineffective assistance of counsel during the penalty phase of his trial, that he was incompetent to stand trial, and that he has an intellectual disability that renders him ineligible for execution under the Eighth Amendment. Brown challenges the district court’s denial of habeas relief and seeks to expand the certificate of appealability to include three additional claims. We have jurisdiction under 28 U.S.C. §§ 1291 and 2253. We affirm the district court’s denial of Brown’s habeas petition and decline to expand the certificate of appealability. I. BACKGROUND The facts, as set forth by the California Supreme Court on direct review in People v. Brown, 73 P.3d 1137, 1147–53 (Cal. 2003), are summarized as follows. A. Guilt Phase In November 1988, Andrew Lamont Brown was determined to steal deep-dish tire rims from a truck. At the time, Brown was living “off and on” in a home with Mark 6 BROWN V. BROOMFIELD Bender, Broderick Fields, Andrew White, Percell McClendon, and others. Brown asked Levi Gardner if he wanted to buy some deep-dish tire rims. Gardner replied that he would have to see them before committing to the purchase, and Brown said he could obtain some. Brown told White that he “was going to do a jack move”—rob someone at gunpoint—“to get some rims,” and invited White to join him. White declined. On November 11, 1988, Brown, Fields, Bender, and McClendon drove around in Bender’s Oldsmobile Cutlass, looking for deep-dish rims to steal. That night, seventeen- year-old Christina Ramirez was driving her husband’s 1985 red Nissan truck which had a Kenwood brand stereo and amplifier and distinctive deep-dish tire rims, each bearing small decorative holes and painted red to match the truck. Brown spotted Ramirez’s truck and exclaimed, “[t]hose are the ones we need.” They made a U-turn and followed the red truck for two traffic lights. Ramirez was driving alone in the truck. When she stopped at a red light, Bender pulled up behind her. According to McClendon’s testimony, Brown jumped out carrying a .38-caliber pistol, ran to the driver’s side of the red truck, and fired one shot through the window, shattering it. Brown then pulled Ramirez out and got into the truck from the driver’s side, while Fields got in from the passenger side. The two cars left the scene. Several individuals witnessed the incident. Juan Williams, whose Mercedes Benz stopped directly behind Bender’s Cutlass, described seeing a young Hispanic male between five feet three inches and five feet six inches tall running up to the driver’s side of the red truck, throwing the victim from the truck, and driving off in it. Williams testified that he did not see a second man enter the truck on the passenger side, although a police officer later testified at BROWN V. BROOMFIELD 7 trial that, on the night of the murder, Williams reported seeing two men running up to the truck. Rena Stanfill’s car was stopped at the red light behind Williams’ Mercedes. Stanfill saw two men exit from a mid- sized “American car” in front of the Mercedes and run to the red pickup truck. According to Stanfill, an African American man about five feet ten inches tall ran to the driver’s side of the truck and pulled a woman out, dropping her so that she struck the pavement face-first. 1 A second man, who was either Hispanic or African American, jumped into the passenger side of the truck. Stanfill saw the two men leave the scene in the truck. Because she was driving with her windows rolled up and radio on, Stanfill did not hear the gunshot. Ramirez suffered a single gunshot wound to the neck. The bullet entered the left side of her neck, traveled downward, and lodged in her spine. Ramirez died from her injuries on December 21, 1988. The bullet retrieved from her body was consistent with having been fired from a .38- caliber handgun. Around 11:45 pm that night, Mark Bender, Fields, and McClendon arrived at Perry Bender’s home. Mark was visibly upset and blurted out: “I know he shot her. I know she is hurt bad.” Soon after, Brown arrived in Ramirez’s red truck, playing loud music on the stereo. Brown had a .38- caliber handgun. When Perry asked how he had obtained the truck, Brown replied that he gotten it in Riverside and that he “[s]moked the bitch.” Sometime between 11:00 p.m. and 1:00 a.m., Gardner’s brother saw Brown sitting in a red truck 1 Brown and Broderick Fields are both African American and stand approximately six feet tall. 8 BROWN V. BROOMFIELD with a camper shell and deep-dish rims in front of Harb’s Liquor Store/Market, the stereo playing loudly. Brown asked him to tell Levi Gardner that he had some “deeps” for Gardner. The next day, Brown offered to sell a single deep-dish rim to Gardner for $50. The rim was painted red and had circular holes in it. Gardner asked to see all four rims before committing to the purchase, so they drove to a remote location in the hills and came upon a red pickup truck down a dirt road. The truck had deep-dish rims and was missing one from the front. Gardner had a “bad feeling” about the deal and declined to buy the rims. Brown offered to lower the price if Gardner helped him remove the other three rims, but Gardner declined. Kevin Davis testified that he had seen the red truck in the Mead Valley hills in November 1988, had seen Brown in a liquor store parking lot with a rim matching those on Ramirez’s truck, and had seen Brown with a .38-caliber handgun. Brown offered to sell Davis a Kenwood brand car stereo, amplifier, and speakers, but he declined. The day after the robbery, Brown, White, and a crowd of people gathered in front of a liquor store in the early evening. According to White, Brown described to the group how he had acquired the red pickup truck, stating he “smoked the bitch” who was driving it. When the group expressed skepticism, Brown swore it was true and invoked his gang, Fruit Town, as proof. Brown asked White to help him remove the rims. Although White had experience in such matters as a car thief, he declined to help because he heard that Brown had shot a person to obtain the truck. Acting on a tip, the Riverside County Sheriff’s Department located and towed Ramirez’s truck from the BROWN V. BROOMFIELD 9 hills. It was missing one wheel and all of its stereo components. Police found heavy scratch marks around the lug nuts, which suggested that someone had tried to remove the remaining wheels with the wrong tool. Blood was discovered in the door jamb on the driver’s side. Brown confronted Rick Kinney, an acquaintance, about the truck’s disappearance, saying: “Where’s my truck at? I took that truck that you’re riding around today, that red truck in the hills, that was mine.” Brown was charged with robbery and first degree murder with special circumstances. At trial, defense counsel presented a theory that Brown was not the shooter, relying on the recollections of two eyewitnesses, Williams and Stanfill, who initially recalled that the shooter was a Hispanic man, not a Black man. Noting that Fields was related to the Bender brothers, defense counsel asserted that the other participants in the crime had closer relationships to each other and suggested they were protecting themselves by pointing the finger at Brown as the shooter. The jury convicted Brown in 1992, finding true a special circumstance allegation that Brown committed the murder while engaged in the commission of a robbery, and two enhancement allegations that Brown personally used a firearm in the commission of his crimes. B. Penalty Phase 1. Evidence in Aggravation The State presented testimony from several witnesses describing five other uncharged violent offenses allegedly committed by Brown in the same year as the underlying murder. Three of the alleged crimes involved a carjacking or attempted carjacking by Brown and others using a .38- 10 BROWN V. BROOMFIELD caliber handgun, and one of those robberies resulted in the shooting death of a victim. The uncharged offenses are discussed in more detail infra pp. 38–42. The State also presented testimony from the victim’s family. Susie Barraza, Christina Ramirez’s mother, testified that Christina was seventeen years old when she was shot and killed. Christina and her husband Joe had gotten married less than a month before the crime, and their wedding reception was scheduled for the day after the shooting. After Christina’s death, her mother became afraid to venture out at night and began therapy. Maria Ramirez, Christina’s mother-in-law, testified that nothing was the same after Christina’s death. Her son Joe became depressed, stopped working, and obtained several guns. He stayed in his bedroom for nearly a year, coming out only to eat and go to the bathroom. After threatening suicide and displaying anger, Joe was committed for observation and counseling. Maria and her husband never strayed far from home in order to keep watch over their son. 2. Evidence in Mitigation Brown did not testify at the penalty phase but called several witnesses to raise doubt about his involvement in the uncharged offenses and to present evidence about his childhood abuse and neglect, mental health issues and substance abuse, and chaotic upbringing. Mitigation witnesses included family and friends, a former Department of Social Services (“DSS”) employee, a former principal, and three expert witnesses. Several witnesses testified to the severe physical and psychological abuse Brown witnessed and experienced as a child. Brown’s mother, Catherine Williams, testified that she gave birth to him when she was sixteen years old. They BROWN V. BROOMFIELD 11 lived with his father Oscar Brown, who often struck Williams. Catherine left Oscar after he fired a gun at her while she was holding Brown. Wesley Armstrong, Brown’s uncle, testified that when Brown was five or six years old, Armstrong went to Catherine’s apartment and found Brown alone and apparently crying in a dark closet with the door closed. Later, Brown appeared to be in pain and had bruises and open wounds on his back, as though he had been whipped with an electrical cord or clothes hanger. Brown was later removed from his mother’s custody and placed with a foster family and then with his grandmother, Lula Armstrong McMaryion, under whose care he remained until he turned 17 or 18 years old. When Brown was in kindergarten, a school nurse filed a report indicating that he had old scars on his back and the front of his chest and thighs, some swollen and discolored areas, old scars on and under the surface of his penis, and scabs. Brown explained that his mother’s friend “RC” had whipped him with an extension cord. The report noted that his mother Catherine told Brown the whippings were good for him. Geneva Cofield, Brown’s foster parent, and her daughter Kay testified that when five-year-old Brown came to live with them, he looked unhealthy, malnourished, and had physical injuries that covered most of his body. Some injuries were old and some were new, and included cigarette burns, wounds on his penis, back and buttocks, and injuries that would take up to six weeks to heal. The injuries were reportedly inflicted by Catherine’s then-boyfriend, “RC” or Ricardo Laurie. Defense expert psychiatrist Dr. Chin Choo testified that when she was a psychiatry resident at the Martin Luther 12 BROWN V. BROOMFIELD King Medical Center, she evaluated a seventeen-year-old Brown who had been admitted to the emergency room. On January 16, 1987, Brown was delusional, disoriented, and psychotic, and stated that he had smoked Sherman cigarettes, i.e., cigarettes laced with phencyclidine, or “PCP.” Dr. Choo prescribed Haldol, a psychotropic drug used to correct symptoms of psychosis but could not confirm that it was administered. Hospital notes recorded that Brown said he was paranoid, had used cocaine, and needed sleep. The next day, Brown was alert and cooperative and admitted to drug use. His behavior was consistent with someone coming down from a psychotic state. Dr. Choo testified that Brown’s psychosis could have been the result of his PCP use. Defense expert Dr. Nancy Kaser-Boyd, a clinical psychologist, offered her opinion about the severity of Brown’s childhood abuse, the effects from it, and the treatments Brown should have received. To form her opinion, she reviewed Brown’s DSS records, school records, IQ testing done by neuropsychologist Dr. Vincent Nunno, and interviews with family members. She also conducted personal interviews of Brown and his family members. Dr. Kaser-Boyd testified that Brown was one of the most physically abused children she had ever seen. In addition to the beatings and burnings, Brown was subjected to psychological abuse, including being locked in a dark closet and having his clothes taken away so he could not escape. Dr. Kaser-Boyd opined that Brown showed symptoms of posttraumatic stress disorder (“PTSD”) and explained that children who have suffered a similar level of abuse and trauma generally cannot develop normally either cognitively or emotionally. Such children are at higher risk for drug and BROWN V. BROOMFIELD 13 alcohol abuse and have a much greater degree of anxiety and depression. Brown’s background was consistent with his low school performance and IQ. Tests revealed that his IQ of 77 was within the borderline intelligence level between low average and intellectually disabled. Brown attended six different schools between seventh and eleventh grade because his grandmother allowed him to switch school to be with his friends. Dr. Kaser-Boyd opined that Brown should have been placed in special education in light of his cognitive deficits, hyperactivity, and the trauma he had suffered, but his grandmother was not sophisticated enough to attend to Brown’s special needs. Dr. Kaser-Boyd also opined that with Brown’s history of abuse and trauma, he needed long-term therapy. Though Catherine was told that Brown was hyperactive, she never sought treatment for him. Similarly, school and DSS officials told his grandmother Lula that Brown needed professional counseling, and needed to be placed in special education and to receive treatment for his hyperactivity. Lula did not follow up on these recommendations. Dr. Kaser-Boyd testified that Brown did not have an available or appropriate adult role model or mentor. Defense expert Dr. James H. Johnson, Jr., geography professor and director of the Center of Urban Poverty for Los Angeles County at the University of California, Los Angeles, testified about the educational, financial, and professional disadvantages for young black males in Compton where Brown grew up. Several witnesses also testified about the dangerous neighborhood where Brown was raised on Piru Street in Compton. The neighborhood was a center of drug-dealing and gang activity, with daily 14 BROWN V. BROOMFIELD shootings and other criminal activity. Brown and his grandmother often slept on the floor because they were afraid that gunshots would come through the windows. 3. Rebuttal Evidence and Closing Arguments In rebuttal, the State presented Sandra Thomas, who met Brown in 1987 and viewed him like a little brother. Brown told her about the robberies he committed, like stealing a Suzuki and a Nissan, stripping them down, and selling them. Once she and Brown saw a Suzuki drive by and he said, “I’m going to get that bitch . . . . I’m jacking that.” Thomas described Brown as appearing happy when he talked about robbing people. In closing argument, the prosecutor reviewed the nature and circumstances of the crime and reminded the jury that it had rejected the defense’s argument at the guilt phase that Brown was intoxicated on the night of Ramirez’s murder. The prosecutor also explained that Brown would get excited about robbing people, did not express remorse and instead bragged about the murder, and made conscious decisions to commit the murder and the uncharged crimes. The prosecutor argued that Brown would be a danger to society if he were sentenced to life without parole (“LWOP”), that Brown “is not suffering from mental disease other than being a sociopath,” and described Brown as a “sociopath on substance abuse” who did not deserve sympathy or mercy. The defense argued in closing that the jury should not only be angry with Brown but also with the people who failed him. Defense counsel explained that the murder and the uncharged crimes were committed by the same group, and because of Brown’s low IQ and early substance abuse, it was unlikely that he was the ringleader. Counsel also stated that it was not Brown’s choice to be abused, to grow BROWN V. BROOMFIELD 15 up in a hopeless and violent neighborhood, and to receive none of the adult guidance, education, or mental health treatment he needed. Counsel explained that Brown’s breakdown and hospitalization at the age of seventeen marked the beginning of his involvement in the one-year spree of uncharged crimes that ended in Ramirez’s death. The case went to the jury the afternoon of March 4, 1992. A verdict of death was returned the following day. II. PROCEDURAL HISTORY The California Supreme Court affirmed Brown’s conviction and death sentence on direct appeal. Brown, 73 P.3d 1137. In 2004, the United States Supreme Court denied certiorari. Brown v. California, 541 U.S. 1045 (2004). Brown filed his first state postconviction petition in 2004. Brown initiated this federal habeas proceeding on June 2, 2004, and filed his petition on May 16, 2005. The district court stayed federal habeas proceedings so that Brown could return to state court to exhaust his claims. Brown then filed a second state postconviction petition. On May 23, 2008, the California Supreme Court summarily denied both state postconviction petitions. Brown then filed an amended federal habeas petition with the district court. On December 18, 2017, the district court denied Brown’s motion for an evidentiary hearing, and on February 4, 2021, the district court denied Brown’s petition on the merits. Brown timely appealed. III. STANDARD OF REVIEW “We review a district court’s denial of habeas relief de novo.” Grimes v. Phillips, 105 F.4th 1159, 1165 (9th Cir. 2024). Because Brown filed his federal petition after April 16 BROWN V. BROOMFIELD 24, 1996, the Antiterrorism and Effective Death Penalty Act (“AEDPA”) governs our review. Id.; see 28 U.S.C. § 2254(d). Under AEDPA, we defer to a state court’s decision on any claim that was adjudicated on the merits unless Brown demonstrates that the state court’s decision (1) “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) “was based on an unreasonable determination of the facts in light of the evidence presented in the State court proceeding.” 28 U.S.C. § 2254(d)(1), (2). “We review the last reasoned state court decision.” Scott v. Broomfield, 173 F.4th 1131, 1145 (9th Cir. 2026). Where there has been a summary denial by the California Supreme Court, we apply AEDPA deference to that determination. See Ochoa v. Davis, 50 F.4th 865, 888 (9th Cir. 2022) (“[T]he California Supreme Court’s summary denial of [a petitioner’s] claims—both certified and uncertified—is a decision on the merits and thus entitled to AEDPA deference.”); see also Cullen v. Pinholster, 563 U.S. 170, 187 (2011) (holding that AEDPA deference “applies even where there has been a summary denial”). Under such circumstance, “a habeas court must determine what arguments or theories . . . could have supported [] the state court’s decision . . . .” Harrington v. Richter, 562 U.S. 86, 102 (2011). “A state court’s determination that a claim lacks merit precludes federal habeas relief so long as ‘fairminded jurists could disagree’ on the correctness of the state court’s decision.” Id. at 101 (quoting Yarborough v. Alvarado, 541 U.S. 652, 664 (2004)). “Under California law, the California Supreme Court’s summary denial of a habeas petition on the merits reflects that court’s determination that ‘the claims made in th[e] BROWN V. BROOMFIELD 17 petition do not state a prima facie case entitling the petitioner to relief.’” Pinholster, 563 U.S. at 188 n.12 (quoting In re Clark, 855 P.2d 729, 741 –42 (Cal. 1993)). The California Supreme Court “generally assumes the allegations in the petition to be true, but does not accept wholly conclusory allegations, and will also review the record of the trial to assess the merits of the petitioner’s claims.” Id. (cleaned up); see also In re Figueroa, 412 P.3d 356, 364 (Cal. 2018) (“This court evaluates a petition by asking whether, assuming the petition’s factual allegations are true, the petitioner would be entitled to relief. If no prima facie case for relief is stated, the court will summarily deny the petition. If, however, the court finds the factual allegations, taken as true, establish a prima facie case for relief, the court will issue an order to show cause.” (cleaned up)). For claims that were summarily denied, our review is not limited to whether the petitioner “had made out a prima facie case in his state habeas petition”; instead, we must evaluate the petitioner’s claims “in their entirety to determine whether the California Supreme Court could reasonably reject those claims on the merits.” Montiel v. Chappell, 43 F.4th 942, 957 n.13 (9th Cir. 2022). IV. CERTIFIED CLAIMS 2 A. Ineffective Assistance of Counsel at Penalty Phase— Claim 36 Brown asserts a certified claim of ineffective assistance of counsel at the penalty phase with numerous subclaims. 2 The State argues that Brown is procedurally barred from receiving relief on his certified and uncertified claims. Because we do not find grounds to afford relief on the merits of Brown’s claims, we decline to address whether procedural default would otherwise apply. See Lewis v. Andes, 95 F.4th 1166, 1185 n.11 (9th Cir. 2024); see also Franklin v. 18 BROWN V. BROOMFIELD His claim raises two general areas of concern about trial counsel’s alleged ineffectiveness: the failure to investigate and present important mitigation evidence, and the failure to rebut uncharged acts introduced against Brown and to object to evidence and arguments raised by state prosecutors. Below, we address each of these assertions and their associated subclaims. A defendant has a Sixth Amendment right to the effective assistance of counsel at the guilt and penalty phases of a capital trial. Strickland v. Washington, 466 U.S. 668, 684–87 (1984). To establish a claim of ineffective assistance of counsel, a petitioner must show that (1) “counsel’s performance was deficient,” and (2) “the deficient performance prejudiced the defense.” Id. at 687. “The benchmark for judging any claim of ineffectiveness must be whether counsel’s conduct so undermined the proper functioning of the adversarial process that the trial cannot be relied on as having produced a just result.” Id. at 686. To be deficient, a petitioner must show that his counsel’s representation fell below an objective standard of “reasonableness under prevailing professional norms.” Id. at 688. Federal courts apply a strong presumption that counsel’s representation was “within the wide range of reasonable professional assistance.” Id. at 689. The Supreme Court has not “articulate[d] specific guidelines for appropriate attorney conduct” but has instructed that the reasonableness of counsel’s actions is assessed under the Johnson, 290 F.3d 1223, 1232 (9th Cir. 2002) (“[A]ppeals courts are empowered to, and in some cases should, reach the merits of habeas petitions if they are . . . clearly not meritorious despite an asserted procedural bar.” (citing Lambrix v. Singletary, 520 U.S. 518, 525 (1997))). BROWN V. BROOMFIELD 19 prevailing professional norms at the time of the challenged actions, Wiggins v. Smith, 539 U.S. 510, 521 (2003) (citation omitted), and in view of “counsel’s perspective at the time,” Strickland, 466 U.S. at 689. “Counsel in a death-penalty case has a duty to make reasonable investigations or to make a reasonable decision that makes particular investigations unnecessary.” Scott, 173 F.4th at 1145 (quoting Andrus v. Texas, 590 U.S. 806, 814 (2020) (per curiam)). As the Supreme Court explains, “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.” Strickland, 466 U.S. at 690–91. To establish prejudice, a petitioner “must show that there is a reasonable probability that, but for counsel’s unprofessional errors, the result of the proceeding would have been different.” Id. at 694. “A reasonable probability is a probability sufficient to undermine confidence in the outcome.” Id. “The likelihood of a different result must be substantial, not just conceivable.” Richter, 562 U.S. at 112. Review of ineffective assistance claims under § 2254(d) is “doubly deferential.” Knowles v. Mirzayance, 556 U.S. 111, 123 (2009). “The question ‘is not whether a federal court believes the state court’s determination’ under the Strickland standard ‘was incorrect but whether [it] was unreasonable—a substantially higher threshold.’” Id. (alteration in original) (quoting Schriro v. Landrigan, 550 U.S. 465, 473 (2007)); see also Richter, 562 U.S. at 105 (“The question is whether there is any reasonable argument that counsel satisfied Strickland’s deferential standard.”). 20 BROWN V. BROOMFIELD 1. Counsel’s Failure to Investigate and Present Additional Mitigating Evidence at the Penalty Phase We begin with Brown’s claim that his trial counsel was deficient by failing to investigate and present important mitigating evidence during the penalty phase of his trial. Specifically, Brown contends that despite having information that would have caused competent counsel to investigate further, counsel failed to investigate and present evidence of Brown’s drug and alcohol addictions, his mental decompensation in the year before the murder, history of family sexual and physical abuse, poverty and environmental conditions, and evidence that Brown was not affiliated with any gang. With his state postconviction petition, Brown submitted three new expert declarations addressing evidence of mitigation that, according to Brown, should have been investigated and presented by trial counsel at the penalty phase. Dr. June Clausen reviewed documents regarding Brown’s social, family, educational, and medical histories and provided a social history as well as psychological assessments of Brown in 2005 and 2008. 3 Dr. Pablo Stewart, a clinical and forensic psychiatrist, conducted a psychiatric assessment of Brown in 2007 based on Brown’s documented social, medical, and psychiatric history as well as two interviews with Brown. Dr. Dale Watson, a psychologist specializing in forensic psychology, conducted tests and interviews of Brown in 2002 to evaluate his neuropsychological functioning. The new mitigation evidence also included lay witness declarations from family 3 Dr. Clausen did not interview Brown as part of her evaluation. BROWN V. BROOMFIELD 21 and friends that supported the experts’ summaries of Brown’s background. Dr. Clausen examined Brown’s family history of intergenerational neglect and child abuse. Brown’s mother Catherine had inconsistent access to food and was beaten by her stepfather Laurence. Catherine was also sexually abused by Laurence. She became pregnant with Brown at 14 or 15 years old and was ill for most of her pregnancy and lacked any prenatal care. Catherine eventually moved in with Oscar Brown, who was physically abusive of both Catherine and Brown. Dr. Clausen observed that Brown’s early life was fraught with violence, and he experienced physical abuse as well as a deprivation of food, nurturing, and sense of stability. Brown “suffered physical abuse and neglect at the hands of his primary caretakers,” and was removed from Catherine’s care after school officials reported that he had been physically abused. He was placed into a foster home for approximately nine months. Although Brown saw a psychiatrist six times while in foster care, neither Catherine nor his grandmother Lula followed up on recommendations to treat Brown’s hyperactivity or seek professional counseling for him. Dr. Clausen also discussed the gang environment, violence, and poverty prevalent in Compton during Brown’s childhood living on Piru Street. Brown was often chased and beaten by other children in the neighborhood, and appeared to be a victim of gang bullying. The community and family in which Brown was raised were poverty-stricken. For example, Dr. Clausen noted Brown’s medical neglect and lack of access to prescription medication from medical providers to treat his conditions. 22 BROWN V. BROOMFIELD Agreeing with Dr. Kaser-Boyd, Dr. Clausen opined that “[n]o healthy and supportive adult was available” to guide Brown. Brown was neglected in every way by his caretakers, who lived in a chaotic environment and were not able to attend to his basic needs. Dr. Clausen opined that it was highly likely that Brown was also sexually abused by Laurence, which contributed to his lack of faith in adults. Because of the abuse and neglect, Brown’s “development was arrested and his cognitive and emotional development impeded.” Childhood trauma also impacted Brown’s academic performance and adolescent development. Brown attended at least eight schools from kindergarten through eleventh grade. The frequent change of schools and mental health problems negatively impacted his school performance and academic achievement. Brown received low test scores through sixth grade and performed even worse in middle and high school yet was permitted to progress on through grade levels. Despite his poor academic performance, Brown was never placed in special education classes. Dr. Clausen also discussed Brown’s lifelong substance abuse. Because Brown did not receive treatment despite showing symptoms of PTSD in early childhood and major depressive disorder in adolescence, he self-medicated with drugs and alcohol. Brown began drinking alcohol when he was around eight years old, using and selling marijuana and PCP at age thirteen, and by age sixteen, he was charged with felony possession of PCP and marijuana. Dr. Clausen reviewed reports from friends and family detailing that by the time Brown was sixteen, he was using large amounts of PCP and cocaine and was acting “crazy.” Declarants reported that Brown had developed addictions to alcohol, marijuana, and cocaine and that he had become paranoid and BROWN V. BROOMFIELD 23 delusional. He thought people were trying to kill him and once tried to burn a tattoo from his body using a cigarette lighter. Brown tried to sell cocaine to make money but often used his own supply and would become desperate for more and steal or start a fight to get money. Dr. Clausen concluded that Brown’s symptoms were consistent with anxiety disorder, mood disorder, psychotic disorder, and polysubstance dependence. Brown was genetically vulnerable to the development of psychiatric illnesses and substance abuse issues, and according to Dr. Clausen, Brown’s substance abuse likely exacerbated his mental health conditions. Dr. Stewart conducted a psychiatric assessment of Brown in April and May 2007 to identify the significant factors affecting his mental and psychological development and functioning and to render an opinion as to Brown’s mental state at the time of the murder. Like Dr. Clausen, Dr. Stewart concluded that Brown was genetically vulnerable to the development of psychiatric illnesses and substance abuse issues based on the history of mental illness in his family. Dr. Stewart also agreed that Brown’s substance abuse likely exacerbated his mental health symptoms. Brown’s early use of alcohol and drugs was a common type of self-medication for survivors of childhood victimization. He noted that marijuana in high doses, which Brown was allegedly taking, when mixed with alcohol can cause hallucinations and delusions and that cocaine and that PCP can cause full- blown paranoid psychosis, agitation, and aggression. Dr. Stewart opined that in 1987, the year before the underlying offense, Brown’s “mental stability was noticeably compromised and he appears to have been decompensating at a fairly rapid rate. He began displaying signs of acute mental and emotional disturbance, including 24 BROWN V. BROOMFIELD depression, suicidality, extreme behavioral disorgani