In law, a matter is moot if further legal proceedings with regard to it can have no effect, or events have placed it beyond the reach of the law. Thereby the matter has been deprived of practical significance or rendered purely academic.

Occasionally a court will grant an exception to mootness in cases relating to the public interest. For example, in the 1973 Supreme Court case of Roe v. Wade, challenging a Texas law forbidding abortion, the state argued that the case was moot because plaintiff Roe was no longer pregnant by the time the case was heard. The court granted a hearing anyway, arguing that the public interest was served by deciding the question even if circumstances made it impossible for Roe herself to benefit.