In 1994, 13.9 million UCR index crimes were reported to police.
Crime is reported when police verify that it has been committed.
They are also called Part I crimes. Victim surveys measure the extent of criminal behavior by focusing on its target - the victims. According to the 1994 NCVS, there were 42 million victimizations. Bureau of Justice Statistics on Crime Victimization Self Report Studies Self report studies are designed to allow participants to reveal information about their violations of the law. The basic assumption is that the anonymity of the respondent and the promise of confidentiality backed by academic credentials will encourage people to accurately describe their illegal activities.