American Protective League

The American Protective League (1917-1919) was an organization of private citizens that worked with Federal law enforcement agencies during the World War I era to identify suspected German sympathizers and to counteract the activities of radicals, anarchists, anti-war activists, and left-wing labor and political organizations. At its zenith, the APL claimed 250,000 members in 600 cities.

The APL was formed in 1917 by A. M. Briggs, a wealthy Chicago advertising executive. Believing the United States Department of Justice to be severely understaffed in the field of counterintelligence in the new wartime environment, Briggs proposed to agency officials the establishment of a new volunteer auxiliary, with participants to be neither paid nor to benefit from expense accounts. Briggs was given authority to proceed with his plan by the Department of Justice on March 22, 1917, and the American Protective League (APL) was born.

Although technically a private organization, the APL nevertheless was the beneficiary of semi-official status. The group received the formal approval from Attorney General Thomas Gregory, who authorized the APL to carry on its letterhead the words "Organized with the Approval and Operating under the Direction of the United States Department of Justice, Bureau of Investigation."

Under this directive, the APL worked with the Bureau of Investigation (BOI) — precursor to the FBI — which gathered information for U.S. District Attorneys. APL assistance was welcomed by the BOI, which in 1915 had only 219 field agents, without direct statutory authorization to carry weapons or to make general arrests. Thus the author of a letter to the New York Times claimed membership in the APL and described it as "a volunteer unpaid auxiliary of the Department of Justice" in which he and his colleagues "have been acting upon cases assigned by the Department of Justice, Military Intelligence, State Department, Civil Service, Provost Marshal General, etc."

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