_Sky:

I appreciate what you say about desensitisation.

Unfortunately since I'm not at university anymore I don't have easy access to a lot of the criminal justice journals I used to.

For every piece of research ... there will be another that says a different thing *sigh*. It is a hard thing to measure, simulated situations are so artificial too.

As Maven says, it is the predisposition thing that puts some people over the edge, imho