Most Governments maintain a mechanism to record developments in criminal activity.
The validity of data and the impression that it makes are often of great importance to Governments at the national and international levels. National statistics on crime are, therefore, often criticized for reflecting not trends in crime per se, but the activities of the agencies that record statistics on crime. As a result, official statistics on crime tend to under-report true crime figures, leaving gaps, particularly with regard to types of crime that are not conventional. In response to these concerns, many criminologists and government agencies have conducted self-report surveys and victimization surveys, claiming that these methods give a more accurate picture of criminal activity. Such methods, however, can be reductive.