A mixed-methods analysis of judges’ views and decision-making surrounding scientific evidence in criminal sentencing

Abstract Background: In contemporary criminal justice systems, the integration of bio-behavioral science evidence into legal proceedings poses complex challenges as well as opportunities. As psychiatric and mental health evidence may often not be accompanied by expert testimony, judges in criminal courts may be tasked with alone interpreting and incorporating this evidence into their decision-making processes. Methods: This study investigates how judges–shaped by their views, beliefs, and personal characteristics–approach decision-making processes during sentencing in light of scientific explanations of behavior, as well as how their views on sentencing may be impacted by mental disorder diagnoses. We utilized a mixed-methods approach, including Natural Language Processing techniques (sentiment analysis and structural topic modeling) as well as qualitative analysis, to analyze data from semi-structured interviews with 34 judges from state criminal courts in the U.S. Results: Results revealed varying degrees of belief in scientific determinism among judges, with corresponding sentiment analysis indicating differences in emotional tone across gender, age, geographical region, and professional background. Structural Topic Modeling identified key themes, including determinism, responsibility, treatment needs, and philosophical considerations surrounding punishment. Qualitative analysis enriched these results by unraveling the philosophical and legal considerations that judges grapple with when considering scientific explanations for defendants’ behavior. Conclusions: Findings underscore the nuanced interplay between scientific understandings of behavior, personal beliefs, and judicial decision-making. This study offers valuable insights into the potential complexities of sentencing considerations involving scientific evidence and underscores the need for standardizing how scientific evidence is presented in courts and investing in science education for judges.