Assimilative Crimes Act
The Assimilative Crimes Act, 18 U.S.C. § 13, makes state law applicable to conduct occurring on lands reserved or acquired by the Federal government as provided in , when the act or omission is not made punishable by an enactment of Congress.
The first Assimilative Crimes Act was passed as § 3 of the Crimes Act of 1825.
Prosecutions instituted under this statute are not to enforce the laws of the state, but to enforce Federal law, the details of which, instead of being recited, are adopted by reference. In addition to minor violations, the statute has been invoked to cover a number of serious criminal offenses defined by state law such as burglary and embezzlement. However, the Assimilative Crimes Act cannot be used to override other Federal policies as expressed by acts of Congress or by valid administrative orders.
The prospective incorporation of state law was upheld in United States v. Sharpnack, 355 U.S. 286 (1957). State law is assimilated only when no "enactment of Congress" covers the conduct. The application of this rule is not always easy. In Williams v. United States, 327 U.S. 711, 717 (1946), prosecution of a sex offense under a state statute with a higher age of consent was held impermissible, but a conviction for a shooting with intent to kill as defined by state law was upheld, despite the similarity of provisions of 18 U.S.C. § 113. There seems to be a definite trend to construe 18 U.S.C. § 13 liberally to provide complete coverage of criminal conduct within a federal enclave, even where the offense is generally covered by Federal law.
The Uniform Code of Military Justice (U.C.M.J.), 10 U.S.C. § 801 et seq., because of its unlimited applicability, is not considered an "enactment of Congress" within the meaning of 18 U.S.C. § 13. Military personnel committing acts on an enclave subject to Federal jurisdiction which are not made an offense by Federal statutes other than the U.C.M.J. may therefore be prosecuted in district court for violations of state law assimilated by 18 U.S.C. § 13, even though they are also subject to court martial. However, dual prosecution, it should be noted, is constitutionally precluded by the Double Jeopardy Clause.
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