Funny thing is that my IQ is a little lower than average (it's about 90 last time I got it "properly" tested) and I figured that out when I was something like 12 or 13. I thought "well if you're being hanged upside down and set on fire and stuff, you're going to say you did it just so they will stop even if you did not do it."
Exactly, which is great if all you want is a scapegoat for some crime. But it's not very good when you are trying to collect intelligence that is supposed to save lives.