What data sources asks respondents to reveal an illegal activity in which they have been involved?

Data sources that ask respondents to reveal illegal activities include self-report surveys, victimization surveys, and anonymous online questionnaires. These tools often aim to gather information on drug use, theft, or other criminal behaviors while ensuring respondent confidentiality to encourage honesty. Examples include the National Survey on Drug Use and Health (NSDUH) and the National Crime Victimization Survey (NCVS). Such methods help researchers understand the prevalence and nature of illegal activities within populations.