<P> Prior restraint is often considered a particularly oppressive form of censorship in Anglo - American jurisprudence because it prevents the restricted material from being heard or distributed at all . Other forms of restrictions on expression ( such as actions for libel or criminal libel , slander , defamation , and contempt of court ) implement criminal or civil sanctions only after the offending material has been published . While such sanctions might lead to a chilling effect , legal commentators argue that at least such actions do not directly impoverish the marketplace of ideas . Prior restraint , on the other hand , takes an idea or material completely out of the marketplace . Thus it is often considered to be the most extreme form of censorship . The United States Supreme Court expressed this view in Nebraska Press Assn . v. Stuart by noting : </P>
why are courts so hesitant to allow prior restraint in restricting speech
because it prevents the restricted material from being heard or distributed at all