(often used in the abbreviated forms M.O.
or simply Method
) is a Latin
phrase, approximately translated as "mode of operation
". The plural is modi operandi
("modes of operation
"). It is used in law enforcement to describe a criminal
's characteristic patterns and style of committing crimes. It is also applied in fraud investigation when speaking of behavior patterns that indicate specific types of fraud, e.g., "False identity is a key MO of retail banking sleeper fraud".
The term is also commonly used in English
in a non-criminal sense to describe someone's habits
or manner of working, the method of operating or functioning.
A criminal's MO may also be used in offender profiling, where it can also be used to find clues to the perpetrator's psychology.
The distinction between MO and signature is in the intent. Actions considered consistent with MO can be linked to one of three intended purposes; 1) to ensure the offender's success in committing the crime; 2) to obscure or otherwise protect the offender from being readily identified or; 3) to facilitate or effect the offender's escape. Actions discovered during an investigation which fall into one or more of these categories can be ascribed as MO.