Offenses that require no mens rea generally are disfavored. Some indication of congressional intent, express or implied, is required to dispense with mens rea as an element of a crime.
A man was indicted for unlawful possession of an unregistered machinegun in violation of the National Firearms Act (Act), 26 U.S.C.S. § 5861(d) following the recovery of a weapon from his home. At trial, petitioner testified that the weapon had never fired automatically when it was in his possession, and that he was ignorant of the weapon's automatic firing capability. The district court convicted and sentenced for the offense, rejecting his contention that § 5861(d) contained a mens rea requirement. On appeal, the court of appeals affirmed. The case was elevated to the Supreme Court of the United States by writ of certiorari.
Was mens rea required to commit the crime?
The court reversed and remanded. It held that to obtain a conviction under the Act, the government was required to prove that petitioner knew of the features of his weapon that brought it within the scope of the Act. The court noted that the silence as to the mens rea requirement in § 5861(d) did not suggest a congressional intent that such requirement be eliminated. The court noted that the potentially harsh penalty attached to a violation of § 5861(d) provided further support for the proposition that a mens rea requirement existed.