The criminal defendants in United States v. Sims and United States v. Stitt were both sentenced under the mandatory minimum 15-year prison term provided by the Armed Career Criminal Act, which applies where a defendant had three prior convictions for certain crimes, including “burglary.” Sims and Stitt had each been previously convicted of burglary under state laws, which each defined burglary as including acts against vehicles or structures that were used for “overnight accommodation.” In each case, the district courts held that the Act’s mandatory minimum sentence applied, but the Courts of Appeal for the Sixth and Eighth Circuits both reversed, holding that the states’ inclusion of nonpermanent or mobile structures rendered the definition to be beyond the generic burglary crime contemplated by Congress under the Act. The Court, in a unanimous opinion by Justice Breyer, reversed, holding that the generic concept of burglary covered by the Act extended to any structure that was adapted to overnight accommodation, and there was no reason to exclude vehicles from that scope—particularly given that a person who breaks into a mobile home risks the same potential of a dangerous confrontation as when the person breaks into an apartment or house.