After the jury convicted petitioner Custis of possession of a firearm by a felon and another federal crime, the Government relied on his prior state court convictions for robbery in Pennsylvania and for burglary and attempted burglary in Maryland to support a motion under the Armed Career Criminal Act of 1984, 18 U.S.C. 924(e) (ACCA), which provides for enhancement of the sentence of a convicted firearms possessor who "has three previous convictions . . . for a violent felony or a serious drug offense." Custis challenged the use for this purpose of the two Maryland convictions on the ground, among others, of ineffective assistance of counsel during the state prosecutions, but the District Court held that 924(e)(1) provides no statutory right to challenge such convictions, and that the Constitution bars the use of a prior conviction for enhancement only when there was a complete denial of counsel in the prior proceeding. Custis was sentenced to an enhanced term of 235 months in prison, and the Court of Appeals affirmed.

Held:

1. With the sole exce