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 Pennsylvania, Peeping Tom laws are addressed under the state's invasion of privacy statutes. Pennsylvania law makes it a criminal offense to view, photograph, or record a person in a situation where they have a reasonable expectation of privacy without their consent. This includes situations where a person is fully or partially naked, such as in bathrooms, dressing rooms, or their own home. The law specifically prohibits the use of devices like cameras, video cameras, and binoculars to commit these acts of voyeurism. Additionally, Pennsylvania law considers it a crime to trespass on private property with the intent to watch, spy, or peer into a window or door. The use of drones for voyeuristic purposes would also fall under these prohibitions. These offenses can range from misdemeanors to felonies depending on the circumstances and the presence of aggravating factors, such as prior offenses or the recording of the observed individual.