Dennis v. United States Supreme Court Upholds Smith Act Convictions, Criminalizes Political Advocacy

On June 4, 1951, the United States Supreme Court ruled 6-2 in Dennis v. United States, upholding the convictions of eleven Communist Party leaders under the Smith Act of 1940. The decision effectively criminalized political advocacy, allowing prosecution for teaching or advocating revolutionary ideas even without evidence of imminent illegal action. It represented the nadir of First Amendment protection during the McCarthy era.

Eugene Dennis, General Secretary of the Communist Party USA, and ten other party leaders had been convicted in 1949 for violating the Smith Act’s prohibition against conspiring to “teach and advocate the overthrow and destruction of the United States government by force and violence.” Their trial lasted nine months and produced no evidence of any overt acts or concrete plans—only evidence that they taught Marxism-Leninism and organized party activities.

Chief Justice Fred Vinson wrote for the plurality, dramatically weakening the “clear and present danger” test established in earlier cases. Vinson adopted Judge Learned Hand’s reformulation from the lower court: “whether the gravity of the ’evil,’ discounted by its improbability, justifies such invasion of free speech as is necessary to avoid the danger.” Under this test, even highly improbable threats could justify speech restrictions if the potential harm was grave enough.

Justices Hugo Black and William O. Douglas wrote powerful dissents. Black declared: “Public opinion being what it now is, few will protest the conviction of these Communist petitioners. There is hope, however, that in calmer times, when present pressures, passions and fears subside, this or some later Court will restore the First Amendment liberties to the high preferred place where they belong in a free society.”

Dennis opened the floodgates for Smith Act prosecutions. By 1957, 141 Communist Party members had been indicted and 93 convicted. The decision would later be substantially limited by Yates v. United States (1957), which required proof of advocacy of concrete action rather than abstract doctrine, and effectively ended Smith Act prosecutions.