Federal Crime (noun) – Criminal activity prohibited by federal statute. A federal crime is a crime under the laws of the United States. The same act may be subject to the concurrent jurisdiction of state law, and indeed both the United States and a state or states may independently prosecute and punish the same act, if different aspects of it are an offense under each jurisdiction. Federal crimes must be made criminal by an Act of Congress, which must be within Congress’s powers under the Constitution. Most federal crimes are codified under title 18 of the United States Code, though military crimes are also federal crimes and are codified in the Uniform Code of Military Justice, are in title 10.