In this month’s podcast episode of 12:01: The Death Penalty in Context, DPI’s Managing Director Anne Holsinger speaks with Professors Craig Haney and Frank Baumgartner, and DPI’s Staff Attorney Leah Roemer about the legacy of the US Supreme Court’s decision in Roper v. Simmons and the legal and scientific landscape surrounding the use of the death penalty for young adults ages 18 – 20. Professors Baumgartner and Haney, along with fellow researcher Karen Steele, collaborated on a 2023 study which discusses the legal context and rationale of the Court’s decision in Roper when it barred the death penalty for juveniles under age 18. Ms. Roemer is a major contributor to DPI’s new report, Immature Minds in a “Maturing Society”: Roper v. Simmons at 20.
Professor Haney explains how neuropsychological research influenced the Roper decision by showing that juveniles are less responsible, more impulsive, more easily influenced by external factors, and have less fixed personalities, making them more amenable to rehabilitation. However, recent science shows these same brain development patterns continue well into a person’s twenties. “18‑, 19‑, and 20-year-olds, it turns out, from a neurobiological and neurodevelopmental perspective, are still very much in the process of maturation, indistinguishable essentially from 16‑, 17‑, and 18-year-olds,” says Professor Haney. This continuing brain development led the American Psychological Association to recommend extending the Roper exclusion to these young adults.
Ms. Roemer shares findings from DPI’s research on sentencing trends since Roper: “In the five years after Roper, there were 92 total death sentences for people under 21…But in the past five years, since 2020, there have only been five death sentences for this age group total.” This significant decline means only about one person between 18 – 21 is sentenced to death each year, with the practice isolated to just four counties in three states over the last five years. Approximately 30% of young adults sentenced to death after Roper have already been removed from death row through overturned sentences or commutations.
Professors Haney and Baumgartner discovered profound racial disparities in death sentencing for this age group. “Among those in the late adolescent class aged 18 to 20, only 20% are white. 80% are people of color,” Professor Baumgartner reveals in discussing death sentences handed down to young adults between 1972 and 2021. DPI’s research identified seven states where every single young adult ages 18 – 20 sentenced to death since Roper was a person of color, and three jurisdictions where every person executed in this age group was a person of color. In Texas, 94% of people currently on death row for crimes committed under age 21 are people of color. Professor Haney attributes this disparity partly to the “adultification” of young people of color, where they are perceived as older and more responsible than white peers of the same age, causing jurors to view their youth as less of a mitigating factor.
The panel discusses Marion Bowman, who was executed in January 2025 in South Carolina for a crime he committed at age 20, as an example of how racial bias affects perception of youth. Despite being just 20 at the time of his crime, his trial attorney referred to him as a “man” while calling the 21-year-old white victim a “little white girl.” Mr. Bowman had developed into what the chief psychiatrist overseeing the state’s death row called “possibly the most respected person on death row” with “a nearly spotless prison record,” yet was still executed.
Listen to: Experts Discuss the Legacy of Roper v. Simmons.
To read: Immature Minds in a “Maturing Society”: Roper v. Simmons at 20.
To read Professors Baumgartner and Haney, and Karen Steele’s research: Roper and Race: the Nature and Effects of Death Penalty Exclusions for Juveniles and the “Late Adolescent Class”
