Prior Restraint Law and Legal Definition

A prior restraint is an official restriction of speech prior to publication. Prior restraint refers to an unconstitutional attempt to prevent publication or broadcast of any statement, which is restraint on free speech and free press prohibited by the First Amendment to the Constitution. The ban on prior restraint allows publication of libel, slander, obvious untruths, anti-government diatribes, racial and religious epithets, and almost any material, except if public security or public safety is endangered and some forms of pornography. The theory, articulated by the U.S. Supreme Court in Near v. Minnesota (1931) is that free speech and free press protections have priority, and lawsuits for libel and slander and prosecutions for criminal advocacy will curb the effect of defamation and untruths. Blackstone’s theory on this subject held that liberty of the press depended on having no prior restraints on publications, and not in freedom from punishment when cri minal matter is published.

In 1971, the Nixon Administration went to court to stop publication of "the Pentagon Papers," a series of accounts based on a stolen, classified document entitled, "The History of U. S. Decision-Making on Viet Nam Policy." The Court in New York Times v United States concluded that a prior restraint on publication of excerpts from the Pentagon Papers violated the First Amendment.