Whether a defendant who pleads guilty to being an armed career criminal is precluded from challenging the predicate convictions in a post-conviction proceeding

Question Presented Petitioner was sentenced as an Armed Career Criminal (ACC) over his protests that he did not have three prior violent felony convictions as required for such a sentence. He had pleaded guilty to being in possession of a weapon as an armed career criminal and waived his appeal rights as part of his plea agreement. Is he precluded from establishing in a post-conviction proceeding that the predicate convictions on which the armed career criminal designation was based were not violent felony offenses because he does not seek to vacate his guilty plea? 1