Offender Signature Behavior

Many aspects are used to identify suspect(s) of violent crimes. Signature is a term used to describe the behaviors committed by an offender that serve the person’s psychological and emotional needs. By analyzing and interpreting an offender’s signature behavior, along with other elements such as modus operandi (MO) and victimology, profilers can then behaviorally link cases and develop an understanding of an offender’s motives. Signature is a term that was first used by the American criminal profiler John Douglas, a supervisory special agent with the Federal Bureau of Investigation (http://what-when-how.com/forensic-sciences/offender-signature/). He developed the term to help investigators distinguish offender behaviors that suggest psychological needs from offender behaviors that are a part of the MO. Each offender has their own varied knowledge and skill set that influences the MO. Each offender expresses psychological needs differently. Individual crime scenes contain a multitude of variables that can influence an offender’s actions. Trying to differentiate between a criminal’s signature behavior and their offender signature, can be confusing. The pattern of MO

Conscious or deliberate acts committed by an offender are known as active signature behavior. The offender is in control and wants to leave a psychological impression, they send a message that is clear, wanting that message to be recognized and understood. (Turvey 2012) An example of active signature behavior is notes left at the scene or a specific or repeated victim type. Unintentionally leaving a particular psychological impression is known as passive signature behavior. Passive signature behavior is incidental, the offender is not in control. Usually the offender is unaware that his/her psychological needs were met by his actions. An example of passive signature behavior is obsessive-compulsive behavior, like stalking.(Turvey,