APA Dictionary of Psychology

n. a rapidly growing field representing the intersection of neuroscience and the legal system. It encompasses not only the study of the neural workings of the human brain as they relate to issues of crime, guilt, and punishment but also the emerging applications of imaging technologies within courtroom proceedings. For example, in a murder trial a defense attorney might use a brain scan showing a tumor pressing on the defendant’s amygdala to argue that they couldn’t control their behavior and should be absolved of any criminal responsibility for the act. Similarly, in civil litigation a lawyer might introduce a scan as evidence that their client has a traumatic brain injury.

Despite its increasing popularity and prevalence, neurolaw remains controversial. Many argue that using neuroimaging—originally developed as a diagnostic tool for medical professionals—to “prove” unobservable psychological attributes (e.g., thoughts, feelings, intentions) through brain activity is an invasion of privacy and infringement of freedom of thought that is devoid of scientifically demonstrated accuracy and validity. Others question the implications of neurolaw for such traditional notions as free will, rational choice, and voluntary conduct (actus reus). Proponents, however, point out potential benefits of applying neuroscience findings and techniques to law, such as developing more accurate methods for lie detection and criminal behavior prediction, developing more effective means of criminal rehabilitation, improving sentencing procedures, and detecting stereotypes or biases unconsciously held by potential jurors. See also neuroethics.