Modus Operandi versus Signature

Modus Operandi versus Signature

Modus Operandi versus Signature

Introduction

In general terms modus operandi (MO) signifies those functional components which are important for an offender to successfully commit a crime (Douglas et al, 1992). Because of the fact that an offender during the commission of his crime will try using a similar method, Modus Operandi has been used historically to make a link between the cases. Factors that may include in a Modus Operandi can be the type of victim, location or a time of day that the offender chose to strike, techniques or points for gaining entry, as well as some of the tools that were used to commit the crime.

On the other hand signature aspects are typically those behaviors and actions that go far beyond to what is necessary towards the fulfillment of the offender's psychological need and to commit a crime. Signature as the name itself suggests are quite stable over time and are witnessed throughout the series of a crime scene and is unique to each offender, and although from crime to crime there might be a subtle difference, there is always an evident theme. As the theme itself represents the psychological need of the offender and reflects and is based heavily upon the offender's fantasies and desires. When investigators discover something rare in a murder, and recognize it again in another murder, a few weeks later we are dealing with a lone killer.

Modus Operandi (MO) is a Latin word which means the method of operation. It means the techniques, strategies and tools used by the criminal while committing a criminal activity. Modus Operandi of a criminal changes and is modified as per his experiences. It is described as patterns of repetitive activities which are devised through a thought process and behaviors that proceed after and during the criminal activity. A criminal can utilize specific weapons, focus on individuals of specific demographics, and commit crimes on specific time of the day or a specific area or locality (Douglas et al, 1992). All of these support the modus operandi. It is the means of accomplishing or doing a certain task, in case of the criminal, it is his characteristics of devising a plan. Usually, the criminals become attached to their Modus Operandi, the repeatedly target the same kind of individuals, in the same neighborhood and in the same pattern.

A criminal signature, in contrast to MO, does not refer to the pattern or completion of a criminal activity. It refers to a specific personal touch which the criminal uses every time he commits the crime. For example a criminal always tortures his victim, stabs them repeatedly or taking away something as a souvenir or trophy or in some cases leaving behind a particular thing to indicate he has stroked again. These actions are motivated by fantasies of a killer and psychological needs (Keppel & Birnes, 1997). The signature of a criminal remains the same throughout unlike the MO. It is a criminal's way of personalizing his ...