Who was the plaintiff in Schenck v. US?

Schenck v. United States, 249 U.S. 47 (1919)

The plaintiff was Charles T. Schenck, General Secretary of the Socialist Party, who was convicted under the Espionage Act of 1917 of attempting to interfere with the operation of the United States Armed Forces, and who appealed his conviction to the US Supreme Court.

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