Ah yes, the old ticking time bomb scenario. A good plot device for poorly written dramas. The problem here is that no such scenario (of note) has ever occurred in the real world. It just doesn't make sense. Why would one person only know the "key" information? And if you've got him in a bunker, then you're safe from him? If there are others, wouldn't they activate their device the second their comrade was captured/missing/etc. And when do ACTUAL terrorists hide giant WMDs with TIMERS? What sense does that make? If you have them, you set them off immediately, or maybe you trigger it by remote for some sort of ransom thingy? Regardless, the ticking time bomb thing is a device used strictly by lazy writers to give a fixed drama point and tension in their stories. It's never happened in real life, so your construct isn't applicable to our real life debate.
Torture doesn't work. Fact. Why? the information is gathered is completely unreliable. People will say anything to make the torture stop. They'll tell the truth. They'll lie. They'll tell you what they think you want you to hear. THEY WILL SAY ANYTHING. And since you don't know the answer to the question (that's why you're torturing them) you have no way to verify the accuracy of any of it.
As noted above, people who perform the actual interrogations say torture doesn't work. Many more sources, I'm not gonna bother to find them. Please feel free to do so yourself.
(And all of this without even dipping into the moral side of the argument)
