Jack Bauer has the luxury of being right or mostly right when he tortures people.
In the movies, the good guys know with near-perfect certainty that the bad guy knows where the bomb is, and there is only just enough time to get the information - thus, torture. If real-world torture worked under similar certainty, few people would be against it.
If one person tortures one other person and as a result found the bomb, he probably wouldn't get a very hard sentence. But in reality (as I understand it, I'm not exactly a subject matter expert), you'd be trying a guy who tortured 50 guys, 49 of which didn't know anything (or didn't break) or fed you disinformation, and then one guy who told you something actionable, that you plausibly could (but perhaps not) have learnt through other channels.