A bill to modify the insanity defense in the Federal courts, and for other purposes.

Amends the Federal criminal Code to make it a defense to a Federal prosecution that at the time of the offense, the defendant, as a result of mental disease or defect, did not understand the wrongfulness of his conduct.

Places the burden of proof of insanity on the defendant.

Authorizes a special verdict of "not guilty only by reason of insanity."

Amends the Federal Rules of Evidence to prohibit expert witnesses from offering opinions on the issue of the insanity of the defendant.

Provides for an initial screening examination to determine whether there is reasonable cause to believe that the defendant lacks competency. Allows for a more thorough examination of the defendant if the initial results suggest incompetency. Requires a hearing on the issue of competency and further examination on the issue of the likelihood the defendant's recovery. Allows for appropriate treatment if necessary. Requires in-patient treatment only when the defendant is dangerous, likely to flee, or in custody.

Transfers to State officials for State civil commitment certain defendants who have received the maximum treatment under this section or are found incompetent with no substantial probability of improvement.

Allows a person serving a sentence of imprisonment to be transferred to a mental institution upon a showing of clear and convincing evidence that the prisoner is in need of treatment.

Establishes Federal commitment procedures for persons found "not guilty only by reason of insanity". Provides for a special examination of violent offenders in order to determine their dangerousness.