The Abrams v. United States case in 1919 revolved around the First Amendment, specifically freedom of speech and expression during wartime. The defendants, including Jacob Abrams, were Russian immigrants who distributed leaflets criticizing U.S involvement in World War I and calling for a general strike against ammunition production intended to be used against the Russian Revolution. They were convicted under the Espionage Act of 1917 which made it a crime to interfere with military operations or support America's enemies during wartime. In a 7-2 decision, the Supreme Court upheld their convictions stating that their actions presented a "clear and present danger" to national security by potentially disrupting war efforts. This case is notable for Justice Oliver Wendell Holmes Jr.'s dissenting opinion where he argued that unless there was an immediate threat to safety, government should not punish people for expressing opinions that deviate from societal norms - this concept later became fundamental in free speech jurisprudence.

In the dissenting opinion for Abrams et al. v. United States, Justice Oliver Wendell Holmes Jr., joined by Justice Louis Brandeis, argued that the defendants' actions did not present a "clear and present danger" to the U.S government's war efforts during World War I - a standard he had previously articulated in Schenck v. United States (1919). He believed that their leaflets criticizing American intervention in Russia were an exercise of free speech protected under First Amendment rights rather than criminal acts inciting resistance to the war effort or insubordination among military personnel as charged by prosecutors. Holmes contended that marketplace of ideas should be allowed to flourish without undue interference from government authorities unless there was an immediate threat to national security or public safety. The justice also emphasized his belief in open debate and tolerance for differing viewpoints as fundamental principles underlying democratic governance.