Apparently NOT! How could it violate it if it isn’t punishment?
Last night, Supreme Court Justice Antonin Scalia granted his first broad-based television interview, to Lesley Stahl on CBS’s 60 Minutes. There he explained that the torture of detainees does not violate the 8th Amendment’s ban on “cruel and unusual punishment” because, according to Scalia, torture is not used as punishment:

STAHL: If someone’s in custody, as in Abu Ghraib, and they are brutalized, by a law enforcement person — if you listen to the expression “cruel and unusual punishment,” doesn’t that apply?

SCALIA: No. To the contrary. You think — Has anybody ever referred to torture as punishment? I don’t think so.

STAHL: Well I think if you’re in custody, and you have a policeman who’s taken you into custody–

SCALIA: And you say he’s punishing you? What’s he punishing you for? … When he’s hurting you in order to get information from you, you wouldn’t say he’s punishing you. What is he punishing you for?

Watch it: