Prosecutors pursued Scales' case because he specifically advocated violent political action and gave demonstrations of martial arts skills.

The act does not punish espionage, sabotage, physical violence or actual attempts to overthrow the Government.

And no reasonable person can believe that the Communists are sufficiently persuasive in this country to create any "immediate" likelihood of success for their subversive ideas.In a letter to the Times, Rep. Francis E. Walter, chair of the House Un-American Activities Committee, countered:[6] It was not speech on the part of Junius Scales that led to his trial and conviction.

It was his cold, calculated act of joining the Communist party [sic], remaining a member of it for many years and holding in it official posts which gave him an active role in the direction of an organization which, you tacitly admit in your editorial, is characterized by its "secret, conspiratorial nature and domination from abroad.President John F. Kennedy commuted Scales' sentence on Christmas Eve, 1962.

Scales is the only Supreme Court decision to uphold a conviction based solely upon membership in a political party.