The insanity defense presents many difficult questions for the legal system. It attracts attention beyond its practical significance (it is seldom used successfully) because it goes to the heart of the concept of legal responsibility. “Not guilty by reason of insanity” generally requires that as a result of mental illness the defendant was unable to distinguish right from wrong at the time of the crime. The many difficult and complex questions presented by the insanity defense (...) have led some in the legal community to hope that neuroscience might help resolve some of these problems, but that hope is not likely to be realized. (shrink)