This paper examines how behavioral genetic evidence has been used in criminal cases to shape ideas of violence, intent, and legal responsibility. Focusing on the case studies State v. Waldroup (2011) and State v. Yepez (2015), it analyzes how courts reached different conclusions regarding the admissibility and influence of MAOA-L gene evidence. The paper argues that the legal significance of behavioral genetics depends largely on how judges and juries interpret scientific legitimacy rather than on the gene itself. It also explores how genetic explanations of violence risk reinforcing biological determinist thinking while drawing attention away from structural factors such as abuse, trauma, and poverty. Ultimately, the project demonstrates the challenges of applying population-level behavioral genetics research to individual criminal defendants within the justice system.
About the Author
Violet Webber is a fourth-year student at the University of California, Los Angeles, double-majoring in Psychobiology and Neuroscience with a minor in Society and Genetics. Her academic interests center around the mechanisms of the mind and human behaviors, with an emphasis on how scientific research shapes public policy and systems of care.