psychotic killers

Last night my friend and I had watched TV. It was some old horror movie with some psychotic killer who was running around and killing the people. After the movie we had little argument about those kinds of people. So, I am interested to know are they the victims of child abuse or something like that. Is that the reason why they kill?

Well it is not so simply. It is a little hard to explain, but people with child abuse history are potential psychopaths. Education and environment have a great influence on young person, and if they are not appropriate everything is possible. But there are other factors like inherited diseases, drug and alcohol abusing during adolescence or infection caused by a virus.