Using Neuroscience in Criminal Law

Abstract

Recent developments in neuroscience and brain imaging technology have substantially increased our knowledge of the human brain. The knowledge gained has been applied in a wide variety of disciplines, including the legal system. Although brain imaging evidence has been offered in civil cases, it has been used more extensively in criminal cases. In criminal matters, neuroimaging has been offered with respect to a number of issues, including competence to stand trial, competence to waive essential rights, right to compulsory examinations, criminal responsibility, mitigation in penalty phase litigation, and claims of actual innocence. Some generalizations are possible at this point. CT scans and MRI images as proof of disease or trauma have been readily admitted. Courts have been far more guarded about scans, such as PET and fMRI, when offered as the basis for inferences about broader issues such as competence, insanity, or criminal responsibility in general. Somewhat more liberal standards have been applied to offers of mitigating evidence in death penalty cases. Courts, in ruling, have focused on reliability standards as well as relevance and probative/prejudicial considerations. On the basis of the experience to date, it is fairly predictable that the use of brain imaging, as it continues to improve, will increase in the traditional areas noted above as well as make inroads in some areas where caution and skepticism prevails at this point. In addition, it is possible to envision many potential uses of neuroscience in changing and improving the way the criminal justice system operates and the way traditional roles are carried out. It is reasonable to expect, however, that change of this type is not likely to occur easily in view of the legal system’s reliance on traditional roles, methods and procedures.