The Supreme Court appeared deeply divided Wednesday over just how much due process Guantanamo Bay detainees deserve in challenging their imprisonment — and how much they already have.

Twice before, related issues have gone before the high court, and twice the Court has ruled in favor of the detainees. But on Wednesday, that trend seemed in jeopardy, as justices weighed the impact of a law passed by Congress last year that stripped U.S. courts of jurisdiction to hear habeas corpus appeals from detainees and established a limited appeal process.