Peeping Tom laws—also known as voyeurism laws or invasion of privacy laws—generally make it illegal and a criminal offense to peek into windows or doors on private property to view a person who is fully or partially naked for the purpose of sexual desire or gratification.

Peeping Tom laws vary from state to state and some states require that the victim not realize he or she was being viewed and that the victim had a reasonable expectation of privacy (was in a place where it was reasonable to expect privacy). And some states specifically address the use of unmanned aircraft (drones), cameras, video cameras, and binoculars in connection with such peeping. Some state statutes specifically prohibit peeking into bathrooms, dressing rooms, showers, and baths. And some states characterize this criminal offense as trespassing with the intent to peer or peep.

Peeping Tom laws are located in a state’s statutes—often in the penal or criminal code.

In California, Peeping Tom laws are addressed under the state's invasion of privacy statutes. California Penal Code sections 647(j) and 647(k) make it illegal to invade someone's privacy with the intent to invade their personal privacy for sexual gratification. This includes looking through holes or openings into areas where a person has a reasonable expectation of privacy, such as bedrooms, bathrooms, changing rooms, and similar private spaces. The law also covers the use of any device, such as a camera or drone, to view or record someone without their consent in situations where they have a reasonable expectation of privacy. Additionally, California law considers it trespassing if someone enters another person's property with the intent to commit any type of invasion of privacy. Violations of these laws can result in misdemeanor or felony charges, depending on the circumstances and the presence of aggravating factors, such as prior offenses or the recording of the observed individual.