Aggression Types and Criminal Behavior
By Michael W. Decaire

Psychology traditionally has defined aggression as behavior against another that intentionally inflicts harm (geer, 1990). This definition, though sufficient for many applications of the word, is not specific enough for the comprehensive understanding of aggressive behavior.

Moyer (1976) identified eight distinct kinds of aggression that can be found in some form it virtually all species, including human behavior. Moyers types are:

(1) Predatory Aggression: our motivated attack behaviors. This aggression is directed to natural prey and is deeply routed in our ancestors hunting behavior. Today it can be seen in the behavior of normal individuals as hunting. Forensic implications: A variety of deviant and abnormal subjects may see others humans as lesser beings. The deviant, which may include narcissists, could see others as non-equals and may not have any moral issues with stealing or hurting such individuals. The psychopath cannot see through the eyes of others and may also not consider them as equals. Such an individual may not have moral qualms with seriously injuring or even killing others.

(2) Intermale Aggression: physical violence or submissive behavior displayed by males towards each other. Forensic implications: these intermale drives could be an explanatory framework for the high rates of intermale violence. Possible causes for such violence could be perceived competition for resources and ego threats that one male feels is being created by a second male.

(3) Fear-Induced Aggression: responses believed to be biologically programmed into us so that we act in an aggressive manner towards any form of forced confinement. Forensic implications: such aggression could be a major issue to prison environments. If already aggressive individuals are placed into an environment that fosters aggression via confinement violence risk may be increased.

(4) Territorial Aggression: threat or attack behavior displayed towards an invasion of ones territory or the submissive-retreat behavior displayed when confronted while intruding. Forensic implications: invasion of ones territory can include much more then property. A believe that one is encroaching on ones status could also be considered an invasion. The loss of power in relationships that can lead to spouse abuse could possibly be explained by this aggression model.

(5) Maternal Aggression: aggressive behavior put forward by females (and most likely males as well) when an intruder is in the presence of ones children. Forensic implications: none other then crimes explained by the situation that the definition gives.

(6) Irritable Aggression: aggression and rage directed towards an object when the aggressor is frustrated, hurt, deprived, or stressed. As a result one may aggress towards objects as an acceptable outlet of the aggression. Forensic implications: some individuals whom do not use, or have available, appropriate outlets could have a spill over of aggression onto others.

(7) Sex related aggression: aggressive behavior that is elicited by the same stimuli that elicits sexual behavior. Any person who can evoke sexual desire can equally evoke aggression via jealousy, etc.. Forensic implications: besides the obvious jealousy-violence reactions, some individuals may for one reason or another come to associate sexual desire with violence and dominance. This association could possibly explain a number of violent sexual acts that occur.

(8) Instrumental Aggression: aggressive behavior displayed because it previously resulted in a reward. Much of human aggression seems to be related to this. Forensic implications: a possible theory for a number of crimes. If one has received an reward (money, sexual gratification) due to a deviant aggressive act that they had performed they will be conditioned towards committing that act again when they are motivated to obtain that previously possessed reward.

Geen, R. G. (1990). Human Aggression. Pacific Grove, CA: Brookes/Cole.
Moyer, K. E. (1976). The Psychology of Aggression. New York: Harper & Row.