The federal government (plaintiff) prosecuted Derek Arrington (defendant) for forcibly assaulting, resisting, opposing, impeding, intimidating, or interfering with three United States Park Police officers in the performance of their duties, in violation of 18 U.S.C. § 111(a), and for using a deadly or dangerous weapon to do so, in violation of § 111(b). Violations of § 111(b) are subject to enhanced penalties. The trial evidence established that, in the course of a routine traffic-violation stop, the officers observed suspected drug paraphernalia in Arrington's car. The officers testified that when Arrington refused their request to step outside the vehicle and instead moved his hand toward the gearshift, they reached into the car and tried to hold Arrington down. Arrington grabbed the gearshift, shifted into drive, and floored the car's engine, taking off with all three officers still reaching into the car. Two officers were able to shake lose, but Arrington dragged the third officer through an intersection before the officer pulled free and fell to the ground. Arrington disputed the officers' testimony, denied having had physical contact with any of the officers, said that none of the officers was reaching into the car when he drove off, and contended that he was only trying to escape arrest. The jury convicted Arrington. Arrington appealed to the District of Columbia Circuit Court of Appeals, contending that the government failed to prove that he intended to use his car in a deadly or dangerous manner.