Mens Rea and Insanity

Two developments in the administration of criminal law call for a closer examination of the relationship between mens rea and insanity. The first is the practice of bifurcating trials into a guilt phase and an insanity phase. The new Maine Criminal Code, for example, allows the defendant to elect such a procedure. The second development is the increasing willingness of courts to admit evidence of the accused's mental disease or defect as probative of whether he possessed the culpable state of mind, or mens rea, which must be proven as one of the elements of the crime charged. When the accused chooses the bifurcated trial, the Maine Code bans such evidence from the guilt phase of trial. This Comment contends that the question whether a legally insane person can possess the requisite criminal mens rea depends upon the type of mental disease or defect at issue. In so doing this Comment will elucidate some of the problems which the relationship between mens rea and insanity poses for bifurcation and for the doctrine of subjective liability.