A bill to amend title 18 of the United States Code to clarify and modify the criminal law with respect to persons alleged to be insane at the time of the alleged commission of Federal offenses, and for other purposes.

Amends the Federal criminal code to authorize a special verdict of "not guilty by reason of insanity" for any defendant who at the time of the offense was laboring under such a defect of reason, from disease of the mind, as not to know the nature and quality of the conduct required for the offense or not to know the criminality of such conduct.

Places the burden of proof of insanity on the defendant.

Directs the court to commit such person found "not guilty by reason of insanity" if he is presently suffering from a mental condition whereby his release would create a substantial danger to himself or to the person or property of another.

Allows for a verdict of "guilty but mentally ill," if the defendant was mentally ill at the time of the offense, but not so mentally ill as to constitute insanity. Allows for treatment for such individual, followed by completion of any remaining prison sentence.