| When you watch your favorite CSI TV show, you | | | | An MO may evolve over time as the perpetrator |
| may have heard of the terms, MO, or modus | | | | finds better ways to commit murder or other kinds |
| operandi, and signature that a perpetrator uses when | | | | of crimes. This may include changing his mode of |
| committing a crime. What is an MO and how does it | | | | entry, ploy, disguise, or the time when the attacks |
| differ from a criminal's signature? | | | | occur. He will modify his methods to become more |
| In this article, we will elaborate on the differences | | | | effective and help him avoid being detected. |
| between these two terminologies so that when you | | | | On the flipside of an MO, a signature refers to an act |
| watch your favorite detective show, you will have a | | | | that has nothing to do with completing the crime or |
| better understanding of what the characters are | | | | getting away with it. Signatures are important to the |
| talking about. | | | | perpetrator in a personal way. Torturing the victim, |
| Modus operandi, aka MO, or method of operation, | | | | repeatedly stabbing the victim, postmortem |
| refers to the tools and techniques that a crook uses | | | | mutilation, and the removing of souvenirs or trophies |
| to commit a crime. This concept is very ancient. In | | | | are examples of signatures. These actions are |
| fact, this concept dates back 19th century England | | | | motivated by a killer's fantasies and psychological |
| when a police constable, Major L.W. Atcherley of the | | | | needs. |
| West Riding Yorkshire Constabulary of England, | | | | Unlike an MO, the perpetrator's signature does not |
| developed a 10-point system for identifying a | | | | change. His signature may be refined over time, but |
| perpetrator's MO. Scotland Yard later incorporated | | | | the basic signature stays the same. For instance, if a |
| many of his techniques that are still in use today. | | | | serial killer poses his victims in particular manner with |
| The following factors are considered when identifying | | | | a crucifix on the chest, details like candles, bracelets |
| a perpetrator's MO: | | | | or other ceremonial objects may be included at a |
| - Place of the crime | | | | later time. The signature has changed, but its basic |
| - Point of entry | | | | theme and form stay the same. |
| - Method of entry | | | | The driving force of a signature is the reason for its |
| - Tools used during the criminal act | | | | stability. The perpetrator's signature takes it origin |
| - Kinds of objects removed from the scene of a | | | | directly from his fantasies. These fantasies develop |
| crime | | | | at a young age and are refined into an obsession |
| - Time of day when the crime occurred | | | | from years of mental rehearsal. During the crime, the |
| - The culprit's alibi | | | | perpetrator forces the victim to respond in accord |
| - The culprit's accomplices | | | | with his fantasy. The signature is used only by the |
| - Mode of transportation to and from the scene | | | | culprit to carry out his personal fantasy. Because his |
| - Unusual characteristics of the crime, such as killing | | | | fantasy never changes, the signature stays the |
| the house cat or leaving behind a note or object to | | | | same. |
| challenge police | | | | The next time you watch CSI and hear of the terms |
| All these factors address the culprit's method of | | | | MO and signature, you will have a better |
| doing things. He finds it necessary to do these things | | | | understanding of their definitions. |
| as part of committing the crime. | | | | |