Criminal Investigative Psychology is the area in Forensic Psychology that is least likely to be acknowledged. The majority of people see this as merely a criminal justice area of expertise. In actuality, this area is strongly associated with how the human mind works. Psychologists can apply their knowledge of human motivation and behavior to areas in the criminal-investigative arena. The criminal profile creates a psychological profile or picture of a suspect based on what he / she knows about motivation, mental illness, and also human behavior. The best place to begin getting an idea of a criminal's mind is often at the scene of a crime.

Investigators pay particular attention to the things done at the scene or to the victim and also to the things not done. These observations can lead to a behavioral profile of the yet unknown suspect. Once the behavioral profile is done, the profile can then compare this to other criminals or mental patients with the same basic characteristics. It is generally very difficult to get professional hands-on experience on how to be a profile. Police have been able to catch a wide array of people using pro filers, including serial killers. Once criminals have been taken into custody, pro filers can learn even more about the criminal mind and can find possible motives, verify motives, and / or assess the defendant's state of mind.

The police psychologist does more hands-on work with officers and victims as opposed to criminals. He / she helps officers to get through crisis situations through counseling, evaluates potential new employees in departments, and also helps victims with what has happened to them. This type of psychologist needs experience with psychological assessment and psychological testing. The specialty of Psychological Autopsy Expert is not often discussed in public, although it is actually frequently relied upon. One example is when a person dies and the insurance company does not want to pay. The company will claim this was a suicide, not a natural or accidental death.

The psychologist may then evaluate the deceased recent mental condition based on third party statements and on medical and / or psychological records.