Sotomayor dissenting: "Today, the Court puts bump stocks back in civilian hands. To do so, it casts aside Congress's definition of 'machinegun' … When I see a bird that walks like a duck, swims like a duck, and quacks like a duck, I call that bird a duck. A bump-stock-equipped semiautomatic rifle fires 'automatically more than one shot, without manual reloading, by a single function of the trigger.' Because I, like Congress, call that a machinegun, I respectfully dissent."