Descamps v. United States

*257The Armed Career Criminal Act (ACCA or Act), 18 U.S.C. § 924(e), increases the sentences of certain federal defendants who have three prior convictions "for a violent felony," including "burglary, arson, or extortion." To determine whether a past conviction is for one of those crimes, courts use what has become known as the "categorical approach": They compare the elements of the statute forming the basis of the defendant's conviction with the elements of the "generic" crime-i.e., the offense as commonly understood. The prior conviction qualifies as an ACCA predicate only if the statute's…