Ive heard of it being done before for detained Iraqis. There was a recent story of US military using music like NIN to torture prisoners. Musicians are pissed that music is used for this purpose.
For me, of course I could call some music that Ive listened to torture because of how bad it is, but im not forced to listen it. I think its wrong, sure you can call some music shitty, but when its used from a completely negative approach I think its crossing the line.