Over the years, freedom of speech and freedom of the press have flourished. The Supreme Court has gradually expanded the scope of what may be considered allowable expression. Traditionally, states were permitted to restrict press or speech "tending to corrupt public morals, incite to crime, or disturb the public peace." In 1937, however, the Supreme Court replaced this standard. In Schenck v. United States (1919), the Court ruled that states can restrict expression only when a "clear and present danger" to the safety of the community can be demonstrated.
In recent decades the Court has required the government to justify restrictions of speech or assembly. According to Brandenburg v. Ohio (1969), any harm or wrongdoing that might result from speech must be shown to be "imminent" or "likely." Symbolic speech or expression, such as burning an American flag, is also protected by the First Amendment.
The doctrine of "no prior restraint" is essential to the freedom of the press. This means that government may not censor or prohibit materials from being published. This was reaffirmed in New York Times Company v. United States (1971). In this case, the U.S. government sued, unsuccessfully, to prevent two newspapers from publishing the now-famous Pentagon Papers. These documents were classified by the Defense Department. But the government could not prove that their publication threatened national security.
The First Amendment also allows criticism of public figures under a wide variety of circumstances. In New York Times v. Sullivan (1964), the Supreme Court ruled that a public person cannot sue an individual or the media for libel (publishing material harmful to that person's reputation). The only exception is if "actual malice," meaning a knowing or reckless disregard for the truth, can be shown.
The same principle applies to freedom of assembly. Federal, state, and municipal governments may regulate certain aspects of a public gathering. For example, they can dictate a time, place, or size of a meeting. But they cannot refuse to grant permission based on what is to be said.
As long as freedom of speech, press, and assembly are secure, an American's right to petition the government is guaranteed. So is the right to openly criticize its laws or policies. Citizens may enjoy these rights as long as they do not harm others or pose a threat to public safety.