Prior restraint refers to a legal principle embodied in the First Amendment to the U.S. Constitution that relates to guarantees of freedom of the press. At the most fundamental level, it provides protection against censorship by the government, and it is particularly relevant to survey research because of legal disputes about the presentation of exit poll results on Election Night.

Prior restraint actually refers to any injunction that would prohibit the publication of information, an infringement on the so-called freedom of the press. Many consider it an especially serious issue because it prevents the dissemination of information to the public, as distinct from an injunction issued after the information has been released that prohibits further dissemination or provides for some kind of relief as in the ...