The Role of Trauma and Mitigation in Capital Punishment

In the early 1990s, the case of Erik and Lyle Menendez captivated the American public, not only because of the brutality of their crime but also because of the defense they presented. The brothers, age 18 and 21 at the time of the crime, were charged with first-degree murder with special circumstances for killing their parents, Jose and Kitty Menendez. These special circumstances made the crime a death-eligible offense. Prosecutors alleged they were privileged young men acting out of greed, but defense counsel presented a very different story, introducing evidence of sustained abuse, including physical, psychological, and sexual abuse by their father starting when they were very young. The brothers argued that years of abuse left them in a state of constant fear and confusion, leading them to a breaking point and resulting in their parents’ deaths. Family members testified to the abuse that they witnessed and recounted stories that the brothers had told them as children during the first of two trials. Ultimately, after a mistrial, and retrial, the Menendez brothers were convicted and sentenced to life in prison without parole. New evidence bolstering the brothers’ claims of abuse has now surfaced, and counsel for both brothers filed habeas petitions arguing for a new trial. On October 24, 2024, Los Angeles County District Attorney George Gascón announced he would ask the court for a resentencing hearing. Since both brothers were under the age of 26 at the time of the incident, they would be eligible for parole if resentenced to 50 years to life.

If there is a new sentencing hearing for the Menendez brothers, the evolving science about the effects of trauma will be a central issue. Numerous sociological and psychological studies have found a powerful link between childhood abuse and later criminal behavior, particularly violent crime. One of the most influential studies on this subject is the Adverse Childhood Experiences (ACE) Study published by Kaiser Permanente in 1998, just two years after the Menendez brothers were sentenced. This study established that individuals who experienced abuse, neglect, or household dysfunction during childhood were at significantly higher risk of developing mental health issues, engaging in risky behavior, and developing substance abuse disorders—all of which are factors associated with an increased likelihood of criminal behavior. Research continues to show that criminal behavior is linked with adverse childhood experiences. A 2013 study found that those with extensive criminal records had a greater number of ACE than their counterparts without criminal records.

Mental health issues and traumatic experiences are often presented as mitigation evidence during capital trials, which are different from other criminal trials, as they have two separate phases of guilt and sentencing. The United States Supreme Court has held that a defendant has the right to present any relevant mitigating evidence in support of a life sentence during the sentencing-phase. Prosecutors may present aggravating evidence in support of a death sentence, such as details of the crime deemed particularly heinous or atrocious. Following the landmark 7-1 decision in Lockett v. Ohio (1978), the Court required states to allow capital sentencing judges and juries to consider all relevant mitigating evidence, striking down Ohio’s law which had only permitted mitigating evidence if it met certain criteria. Sandra Lockett, the defendant in the case, had been sentenced to death in 1975, at the age of 21, with no prior felony convictions. The evidence in Ms. Lockett’s case established that she was, at worst, a getaway driver who did not kill anyone nor intend for anyone to be killed. As a result of the ruling, Ms. Lockett and approximately 100 other death-row prisoners in Ohio were resentenced to life with the possibility of parole. In the case of the Menendez brothers, counsel presented extensive evidence of the abuse that both brothers experienced during their first trial. However, this trial ended in a mistrial when neither jury could reach a unanimous decision. During their second trial, much of this mitigating evidence was not presented, and prosecutors contended that both brothers were lying about the abuse they suffered.

The Death Penalty Information Center (DPI) found that of the 90 people executed from 2020 through October 31, 2024, 76.7% of them had experienced significant trauma, 53.4% had severe mental illness, and 44.4% had low IQ and/or brain damage. Wesley Purkey’s mental health history was marked by an array of severe psychological and neurological disorders, compounded by profound trauma beginning in childhood and worsened by progressive cognitive decline. Sentenced to death in 2004 for the 1998 murder of a teenage girl, Mr. Purkey’s jury did not hear the depth of his mental illness. Diagnosed with schizophrenia and psychosis, conditions with symptoms of delusions and hallucinations, Mr. Purkey had a fragmented grasp on reality. He was also being treated for bipolar disorder and complex post-traumatic stress disorder (PTSD), stemming from “pervasive and extraordinary childhood physical, sexual, and emotional abuse he endured.” One psychiatrist that evaluated Mr. Purkey noted 11 distinct trauma categories, including repeated sexual abuse and assault inflicted by his mother from the age of 10.

As Mr. Purkey aged behind bars, his delusions continued. He held a “consistent belief” that he was going to be executed because of “a grand conspiracy against him” in retaliation for grievances and lawsuits he filed against the Federal Bureau of Prisons. He reiterated that corrections officers admitted to him “all the time” that they knew his legal filings were the “real reason” for his death sentence. A psychiatrist assessing Mr. Purkey’s competency for execution determined that he “lack[ed] a rational understanding for the basis of execution,” and instead “has a fixed belief that he is going to be executed in retaliation for his legal work.” In 2017, Mr. Purkey was diagnosed with dementia, which progressed to Alzheimer’s disease by 2019. Ultimately, the federal government executed Mr. Purkey on July 16, 2020, after a 5-4 overnight decision from the United States Supreme Court cut short judicial review of his legal claims. 

As of October 31, 2024, DPI determined that 16 of the 20 people executed this year, or 80%, had experienced trauma, largely during childhood and adolescence. Florida death-sentenced prisoner Loran Cole, who was executed on August 19, 2024, was one of these individuals. Mr. Cole was sentenced to death in 1995 for the murder of a Florida State University student. Following the governor’s issuance of an execution warrant, counsel for Mr. Cole filed a motion requesting the judge vacate his death sentence, arguing in the motion that the state of Florida is “complicit in the horrific and tragic” abuse that Mr. Cole experienced at the “notorious” Arthur G. Dozier School for Boys. In 1984, at age 17, Mr. Cole was sent to the Dozier School, where he lived through “torturous treatment.” Dozier was a reform school operated by the Florida Department of Juvenile Justice at the time of its closure in 2011. The discovery of numerous unmarked graves on the property provided grim evidence of the harsh conditions, violent incidents, and cruel treatment endured by the children and adolescents sent there. Former students have recounted harrowing stories of abuse and torture inflicted by Dozier staff, sharing these accounts with Florida lawmakers. According to court filings, Mr. Cole’s previously repressed memories of abuse at Dozier resurfaced after he watched a documentary detailing similar experiences suffered by others at the institution. He alleged that during his six-month stay he endured frequent beatings, suffered sexual assault by a guard, and had both legs broken following an attempted escape.

In 2021, 36.4% of executed prisoners experienced the compounding effects of trauma, severe mental illness, and low IQ and/or brain damage, including Lisa Montgomery, whose execution marked the first federal execution of 2021. Ms. Montgomery, a mother of four, killed a pregnant woman and cut her baby out of her stomach. She readily admitted to her crime when police found her with the newborn the following day. Ms. Montgomery’s trial attorney never presented her capital jury with a complete picture of the intense abuse and trauma she experienced throughout her entire life. Instead, he argued that she suffered from pseudocyesis, a phantom pregnancy, and attempted to make an insanity plea. Once Ms. Montgomery moved to appellate proceedings, her attorneys began to unearth the details and significant evidence of her mental illness and traumatic experiences. As a young child, Ms. Montgomery’s family moved in with her stepfather, who built a structure in their backyard where he and his friends sexually abused her. Ms. Montgomery’s own mother prostituted her in order to “pay the bills” and at the age of 18, she was forced to marry her stepbrother, who continued to sexually assault her. Ms. Montgomery’s legal team also found evidence that she had been beaten so badly it had caused a traumatic brain injury. According to a 2018 study, traumatic brain injuries are associated with an increased risk of violence and criminal convictions. Those with a history of traumatic brain injury tend to report significantly higher levels of past abuse, neglect, and trauma compared to individuals who have not experienced a traumatic brain injury. Additionally, these individuals are more likely to experience ongoing challenges with mental health issues and substance abuse.

The jury in 2008 never heard about Ms. Montgomery’s mental health diagnoses: bipolar disorder, temporal lobe epilepsy, complex-post traumatic stress disorder, dissociative disorder, and psychosis. Had this information been presented as mitigating evidence, she may not have been sentenced to death and then executed. The American Bar Association’s most recent “Guidelines for the Appointment and Performance of Defense Counsel in Death Penalty Cases” emphasizes the importance of developing mitigating evidence in capital cases. It states: “[I]t is imperative that counsel begin investigating mitigating evidence and assembling the defense team as early as possible—well before the prosecution has actually determined that the death penalty will be sought.”