Is there a predictable cognitive progression and set of traits that can lead an otherwise law-abiding person to murder? Yes.
Most books about murderers emphasize how they are different from us. In Psychology of Murder I will show how they are similar, how they rationalize what they have done, and the warning signs that if left unchecked can lead any of us to a tragic impulsive choice, killing friends, family members, even our own children. The decision to kill requires only a brief irrational moment in which you feel the other person deserves it.

As you will see, even mass shooters and serial killers often start out on a very normal path but experience a gradual uninterrupted progression toward their evil acts.