Upskirting is the act of secretly or surreptitiously photographing underneath a woman’s dress or skirt. Because upskirting often occurs in public places, laws prohibiting the practice have been challenged on the ground that the victim does not have a reasonable expectation of privacy.

Laws regarding upskirting behavior—including photographing or videotaping a person in a bathroom or changing room—vary from state to state. In some states this conduct is prosecuted as a criminal offense under invasion of privacy, voyeurism, unlawful surveillance, surreptitious recording, disorderly conduct, or public lewdness statutes—depending on the state and its current laws.

Upskirting and the related criminal offenses for which upskirting may be prosecuted are located in a state’s statutes—often in the penal or criminal code.

In Massachusetts, upskirting is explicitly illegal under state law. The Massachusetts Supreme Judicial Court ruled in 2014 that the existing Peeping Tom laws did not cover upskirting, as the victims were not nude or partially nude. In response, the Massachusetts legislature quickly passed a bill to outlaw upskirting. The law, Chapter 272, Section 105(b) of the General Laws of Massachusetts, makes it a crime to secretly photograph, videotape, or electronically surveil another person's sexual or other intimate parts under or around the person's clothing where a reasonable person would believe that the person's sexual or other intimate parts would not be visible to the public. This law applies regardless of whether the person is in a public or private space. Violation of this law can result in a fine and/or imprisonment, and the act is considered a form of sexual harassment.