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 Iowa, Peeping Tom laws are addressed under the state's invasion of privacy statutes. Iowa Code Section 709.21 specifically prohibits 'invasion of privacy - nudity,' making it illegal for any person to knowingly view, photograph, or film another person without consent when the other person is in a state of partial or full nudity and has a reasonable expectation of privacy. This includes situations where the person is in a place where they would expect privacy, such as in a bathroom, dressing room, or their own home. The law also covers the use of any device, including cameras and drones, to invade someone's privacy. Violation of these laws is considered a serious misdemeanor in Iowa. Additionally, if the act is committed for the purpose of sexual gratification, it may lead to more severe charges and penalties. It's important to note that the victim does not need to be aware that they are being viewed for the offense to occur. The emphasis is on the reasonable expectation of privacy and the intent of the individual committing the act.