Peter Kreeft spoke in Dallas last night and commented on the question, "Is torture ever justified?" Suprisingly, his answer was yes.
His answer was given within the context of the ticking time bomb situation: If you knew a bomb was in a city and about to go off, would you torture a person who knew the whereabouts of the bomb? Kreeft's reply is you can torture a GUILTY person in such a situation in order to get the information. A guilty person has forfeited his rights in this scenario. This qualification does not imply that you could torture innocents, e.g. the person's loved ones.
This answer resolves the concern I had, namely, an interrogator would harm the a detainee's child or spouse in order to acquire the high value information. Practically speaking it is unlikely to happen, but I didn't want to hold a position that could justify it.
This isn't to say Kreeft's answer is problem free. I detect two:
1) If human dignity is intrinsic or absolute, then how can a person forfeit it? Forfeiture suggests it is conditional or relative.
2) This problem resembles the thought experiment about whether you should lie to the Nazis if they knock on the door and you're hiding Jews in the basement. Kreeft's answer is you should lie because the Nazis have forfeited their right to the truth. My concern with such answers is that they suggest the rightness or wrongess of an act depends upon its recipient. One would think it would depend upon the intrisnic nature of the act itself, not upon external circumstances. Lying and torture should be right or wrong per se, not because of the situation. Kreeft's way of thinking seems to say, "Whether lying or torturing is wrong depends upon whom you are doing it to." I sound awfully Kantian here...