The above link was from Does Truth Serum Work? at Slate/MSNBC. They contend it doesn't work, no suprise there.
I have wondered though, if the govt doesn't have it's own potions mixed up that isn't let into public knowlege. But those are my musings.
I have not heard of an effective truth serum. But it would seem to me that we must have spent a ton of money on developing such chemicals both during the cold war and during the war on terror. But spending money on research does not equal success. IT does not even follow that such a chemical compound is possible.
My Dad was an expert interrogator. Lots of law enforcement agencies in Ohio would ask Dad to do interrogations on tough cases. All Dad needed was for the subject to talk. Over time Dad, with out ever using any strong arm tactics, could learn the truth. It usually did not take him more than a couple of sessions to get to the truth about what he wanted to know.