Prior restraints—legal prohibitions on disseminating information before publication—are an odious burden on the freedom of expression and come with a “heavy presumption” against their constitutionality. Indeed, they are so disfavored in the law as to be virtually impossible to obtain outside of wartime.
Informal prior restraints—government pressure without formal sanction—are even more unconstitutional than formal ones, as the Supreme Court noted in Bantam Books v. Sullivan (1963). In that case, the Court forbade the Rhode Island Commission to Encourage Morality in Youth from sending threatening letters to book distributors in an attempt to nudge the distributors into not carrying “obscene” material.
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