A victimless crime is an illegal act that typically either directly involves only the perpetrator or occurs between consenting adults; because it is consensual in nature, there is arguably no true victim, i.e. aggrieved party.
Definitions of victimless crimes vary in different parts of the world and different law systems, but usually include possession of any illegal contraband, recreational drug use, prostitution and prohibited sexual behavior between consenting adults, assisted suicide, and smuggling among other similar infractions. However, there is controversy surrounding this. Edwin Schur and Hugo Adam Bedau state in their book Victimless Crimes: Two Sides of a Controversy that "some of these laws produce secondary crime, and all create new 'criminals,' many of whom are otherwise law-abiding citizens and people in authority."
In politics, a lobbyist or an activist might use this phrase with the implication that the law in question should be abolished.
Victimless crimes are, in the harm principle of John Stuart Mill, "victimless" from a position that considers the individual as the sole sovereign, to the exclusion of more abstract bodies such as a community or a state against which criminal offenses may be directed.