FBI History

When the Bureau was established, there were few federal crimes. The Bureau of Investigation primarily investigated violations of laws involving national banking, bankruptcy, naturalization, antitrust, peonage, and land fraud. Because the early Bureau provided no formal training, previous law enforcement experience or a background in the law was considered desirable.

The first major expansion in Bureau jurisdiction came in June 1910 when the Mann ("White Slave") Act was passed, making it a crime to transport women over state lines for immoral purposes. It also provided a tool by which the federal government could investigate criminals who evaded state laws but had no other federal violations. Finch became Commissioner of White Slavery Act violations in 1912, and former Special Examiner A. Bruce Bielaski became the new Bureau of Investigation Chief.

Over the next few years, the number of Special Agents grew to more than 300, and these individuals were complemented by another 300 Support Employees. Field offices existed from the Bureau's inception. Each field operation was controlled by a Special Agent in Charge who was responsible to Washington. Most field offices were located in major cities. However, several were located near the Mexican border where they concentrated on smuggling, neutrality violations, and intelligence collection, often in connection with the Mexican revolution.

With the April 1917 entry of the United States into World War I during Woodrow Wilson's administration, the Bureau's work was increased again. As a result of the war, the Bureau acquired responsibility for the Espionage, Selective Service, and Sabotage Acts, and assisted the Department of Labor by investigating enemy aliens. During these years Special Agents with general investigative experience and facility in certain languages augmented the Bureau.

William J. Flynn, former head of the Secret Service, became Director of the Bureau of Investigation in July 1919 and was the first to use that title. In October 1919, passage of the National Motor Vehicle Theft Act gave the Bureau of Investigation another tool by which to prosecute criminals who previously evaded the law by crossing state lines. With the return of the country to "normalcy" under President Warren G. Harding in 1921, the Bureau of Investigation returned to its pre-war role of fighting the few federal crimes.