Investigative Techniques and Methods

Investigative techniques and methods are the ways investigators work out who committed a crime. Modus operandi, Latin for mode of operating, refers in criminal law to a method of operation or pattern of criminal behavior so distinctive that separate crimes are recognized as the work of the same person. It is used as a basis for admitting evidence of other crimes and is permitted by Rule 404(b)(2) of the Federal Rules of Evidence, so that, for example, an earlier armed robbery with the same unusual disguise and habits can be admitted to prove identity when the evidence is specific enough to identify the defendant uniquely.