Mental abnormalities

Whatever people do, whatever people say there always certain reasons for every human's activity. There is no way for one to do something without any reasons for it. The question about normality of those reasons is not a question of this topic. If talking about psychological point of view to the problem, there are no reasons that would be recognized as invalid reasons. Psychologists say that everything that makes people happy may be recognized as allowed action.
If being subjective, it is a rather wrong point of view, as according to this everything is allowed and it is okay to hurt people in case if someone will feel good about it. There are rules of morality which regulate our actions and those rules are created in order to make us remain people but not beasts. So, nit every reason may be recognized as justifying reason.
In most cases it is the mental abnormalities of criminals that make them breaking laws. They are people of different psychology and a number of things we recognize as terrible they recognize as okay. They are people with defective vision of this world. They are thirsty for something though they don't want to apply efforts in order to get it. They choose the easier way, the way of criminal activity.
There are people who are displeased with political or social order of their countries and some of them try to do something in order to change it but some of them prefer breaking rules and laws of the society. It is the mental abnormalities that make them criminals and provide them with inner right to so what they wont. They are people skillful in finding justification for all the deeds they perform.