Can you blame people for "evil" behaviour.

Define evil first. Then I can comment.

What were you thinking of when you asked this?

I’m really not sure. I consider evil to be any act which is unforgivable. I was thinking about mental disorders, that cause people to have judgement or values outside of the societal norm, either drastically or not so much. I don’t have much knowledge of this sort of thing, to be honest.

So what’s the question?

If a majority (or almost all) of these crimes are commuted by people with some sort of psychological imbalance, can you “blame” these criminals?

Behavior can be controlled. Even a rapist makes decisions about whom to rape and when. That is how we know that if he wished to refrain he could refrain, and that is why, when he is caught, we make him assume responsibility.

There are certain mental illnesses that may confuse volition, but generally these are not prone to violence.

In my opinion, mental disorders, disadvantaged upbringing, chemical imbalances etc. are not causative agents. In my work with severely disabled people, each individual has certain behaviours that are typified by their condition and to one way of thinking they cannot control their actions. However with a little gentle encouragement and appropriate reasoning, they can mostly come to regain control of themselves. There is nothing definitively causative about the mind. Rather, these factors influence the probability of a certain decision being made.

You can blame the person, because their mental state defines the person. A stroke may change a person’s personality, and they are thereafter treated as a different person by every new acquaintance. I believe that every person is responsible for their actions, no matter what their mental state or background is.

The only reason for blaming or not blaming the person is the way in which consequences are determined. If a person of average sanity and intelligence did some things my clients do, they would be in line for strong punishment. The reason we do not do this to those of less than average sanity is because it is ineffective. Encouragement and support is what works, so that is what we do. They still have a choice, but at times many mental factors combine to make the probability of misbehaviour overwhelming. However for someone of average intelligence, strength of will should be enough to overcome whatever urges and “evil” tendencies they may encounter.

Not only can we, but we must blame criminals for their crimes.
If they have a psychological disorder, then that disorder needs to be treated.

If you’re interested in looking deeper into this question, you might want to read what some philosophers have to say on the topic; look into Rousseau and his idea of the “noble savage” for the belief that mankind is inherently good, and read up on the Christian idea of “original sin” for the belief that we are born evil. Those are good starting points for investigation of your general question.