Whether the presumption of mens rea applies to 18 U.S.C. § 924(c)(1)(B)(ii) requiring the government to prove a defendant knew of a firearm's automatic capability before imposing a decades-long mandatory minimum sentence

A person who is convicted under 18 U.S.C. § 924(c) of possession of a firearm in furtherance of a crime of violence or drug trafficking crime, but whose firearm qualifies under federal law as a machinegun , faces a mandatory 30 -year consecutive sentence, rather than the statute’s otherwise applicable 5 -year , 7-year , and 10-year consecutive penalties. Compare 18 U.S.C. § 924(c)(1)(B)(ii) , with id . § 924(c)(1)(A)(i) -(iii). In the D.C. and Eleventh Circuits, the automatic nature of the weapon is a strict liability element , while in the First Circuit , the government must prove the defendant knew it was a machinegun. The question presented is whether the presumption of mens rea applies to 18 U.S.C. § 924(c)(1)(B)(ii) requiring the government to prove that a defendant knew of the automatic capability of a firearm before subjecting the defendant to a consecutive, decades -long mandatory minimum sentence .