Supervisors v. Schenck was a United States Supreme Court case that addressed the issue of free speech. The case involved Charles Schenck, a member of the Socialist Party, who was arrested for distributing leaflets that urged people to oppose the draft during World War I. Schenck argued that his actions were protected by the First Amendment, which guarantees the right to free speech. The Supreme Court ruled in favor of the government, finding that Schenck's actions were not protected by the First Amendment. The Court held that the government could restrict speech if it posed a "clear and present danger" to public safety. The Court reasoned that Schenck's leaflets could have caused people to resist the draft, which would have posed a threat to public safety. The decision in Supervisors v. Schenck established the "clear and present danger" test, which is still used today to determine when the government can restrict speech. The case also established that the government can restrict speech if it poses a threat to public safety.

In the case of Supervisors v. Schenck, the Supreme Court was tasked with determining whether a federal law prohibiting individuals from distributing materials that could be considered as inciting resistance to military conscription during wartime was constitutional. The majority opinion held that it did not violate freedom of speech and expression under the First Amendment because such activities posed a clear and present danger to public safety. However, Justice Field dissented from this decision, arguing that while Congress had authority over matters related to national security in times of war, they should not have been allowed to restrict free speech without showing some direct connection between what is said or written and an imminent threat against public order or safety. He argued further that any attempt by Congress to limit freedom of expression must be narrowly tailored so as only those expressions which are truly dangerous can be prohibited; otherwise it would amount to censorship on all forms of political dissent which he believed violated fundamental rights protected by the Constitution.