18 U.S.C. § 4242
Section 4242 · Determination of the existence of insanity at the time of the offense
Amended 2 times on record
Applied in 102 court decisions — leading case United States v. Velasquez (1989)
Most recently applied in United States v. Richard Austin Williams (June 2023)
Cases citing this section usually also cite 18 U.S.C. § 4241 · 18 U.S.C. § 4243 · 18 U.S.C. § 17
How often courts cite this section
Court decisions citing this, by year.Markers show enactment, consequential amendments, and circuit splits over this section — watch for a citation surge after a change or a disagreement. The dip in the last several years is a data-coverage gap, not a real trend — our corpus holds fewer opinions from the most recent years, so recent citations are undercounted.
(a) Motion for Pretrial Psychiatric or Psychological Examination.—Upon the filing of a notice, as provided in Rule 12.2 of the Federal Rules of Criminal Procedure, that the defendant intends to rely on the defense of insanity, the court, upon motion of the attorney for the Government, shall order that a psychiatric or psychological examination of the defendant be conducted, and that a psychiatric or psychological report be filed with the court, pursuant to the provisions of section 4247(b) and (c).
(b) Special Verdict.—If the issue of insanity is raised by notice as provided in Rule 12.2 of the Federal Rules of Criminal Procedure on motion of the defendant or of the attorney for the Government, or on the court's own motion, the jury shall be instructed to find, or, in the event of a nonjury trial, the court shall find the defendant—
(1) guilty;
(2) not guilty; or
(3) not guilty only by reason of insanity.
Editorial notes U.S. Code · Office of the Law Revision Counsel
Historical and Revision Notes
Based on title 18, U.S.C., 1940 ed., §877 (May 13, 1930, ch. 254, §7, 46 Stat. 272).
Minor change was made in phraseology.
Amendments
1984—Pub. L. 98–473 amended section generally, substituting “Determination of the existence of insanity at the time of the offense” for “Retransfer upon recovery” in section catchline, and substituting provisions relating to motion for pretrial psychiatric or psychological examination, and special verdict, for provisions relating to retransfer to a penal or correctional institution upon recovery of an inmate of the United States hospital for defective delinquents.