Behavioural Genetics in Criminal Cases: Past, Present and Future

Abstract

Researchers studying human behavioral genetics have made significant scientific progress in enhancing our understanding of the relative contributions of genetics and the environment in observed variations in human behavior. Quickly outpacing the advances in the science are its applications in the criminal justice system. Already, human behavioral genetics research has been introduced in the U.S. criminal justice system, and its use will only become more prevalent. This essay discusses the recent historical use of behavioral genetics in criminal cases, recent advances in two gene variants of particular interest in the criminal law, MAOA and SLC6A4, the recent expert testimony on behalf of criminal defendants with respect to these two gene variants, and the future direction of behavioral genetics evidence in criminal cases.

Keywords: Criminal law, genetics, behavioral genetics, behavioral predispositions, neurology, neuroscience, serotonin, SLC6A4, MAOA, Monamine Oxidase A, actus reus, voluntary act, mens rea, insanity defense, mitigating evidence, aggravating evidence, sentencing, liability, Caspi, violence, aggression, antisoc