Advances in genomic research, biobanking and DNA identification technologies are expanding the use of biological and genetic evidence in litigation. The discovery of DNA and one of its functions to transmit hereditary information made it possible to look differently at the theory of a genetic predisposition to deviant behavior. The relevance of the study is due to the fact that the availability and increase of genetic research allows, along with the traditional use of genetic expertise in litigation (search and identification of a criminal, establishment of paternity), to expand the possibility of using the achievements of genetics by the parties to prove other circumstances in court. In this article, the authors analyze the US jurisprudence regarding the possibility of a party using the protection of genetic evidence in order to present a position in justification of the mitigation of punishment for an accused due to her genetic predisposition to criminal behavior. The authors also paid attention to the consideration of the issue of using the results of genetic testing in civil proceedings in order to prove the fact of the influence of the inherited gene on deviant behavior. In carrying out this study, the authors used a significant number of Russian and foreign sources of scientific literature. General and specific scientific methods of cognition, including the formal legal and comparative legal method, were used as research methods