Lackawanna County District Attorney v. Coss, 532 U.S. 394 (2001), was a United States Supreme Court case.

The case concerned a federal prisoner who sought to challenge his current sentence by arguing it was enhanced based on an unconstitutional prior conviction.

A habeas challenge, based on a claim that his trial attorney was constitutionally ineffective, was never ruled on by state courts.

Justice Sandra Day O'Connor wrote the majority opinion of the Court which reversed the decision of the Third Circuit.

[4] The first element was that the petitioner is "in custody pursuant to the judgment of a state court", a status that Coss could not fulfill as he was not serving his 1986 sentences any longer.