[Reizvoll]

you will probably find that many of these killers have a very high IQ.

I don't see any distinction and I don't know where you got the reference to IQ. I think you can be crazy and have a high IQ at the same time, as crazy isn't really the same thing as 'metally handicapped'. Sure, alot of serial killers are way above average IQ, they probably are, but that still doesn't mean they know the difference between right and wrong or know the limit to what they are doing. Some people can just snap if they are put under enough pressure.