The NLRB's Economic Division proved critical in pushing for a congressional investigation into employer anti-union activities, and ensuring that investigation was a success. The Economic Division was deeply aware of employer use of labor spies, violence, and company unions to thwart union organizing, and quietly pressed for a congressional investigation into these and other tactics. Senator Robert M. La Follette, Jr. took up the suggestion, on June 6, 1936, the Senate Committee on Education and Labor established a Subcommittee Investigating Violations of Free Speech and the Rights of Labor chaired by La Follette. Better known as the "La Follette Committee", the subcommittee held extensive hearings for five years and published numerous reports. The committee uncovered extensive evidence of millions of company dollars used to pay for spies and fifth columnists within unions, exposed the culpability of local law enforcement in acts of violence and murder against union supporters (particularly in the Harlan County War), revealed the wide extent of illegal blacklisting of union members, and exposed the use of armed strikebreakers and widespread stockpiling of tear gas, vomit gas, machine guns, mortars, and armor by corporations to use against strikers. Some of the evidence the committee used was provided by the Economic Division, and the investigation proved critical for a time in defending the agency from business and congressional attack.