 Charlie Siringo, another former employee of the agency, had no sympathy for labor, yet wrote books about his experiences as a Pinkerton Detective that were so objectionable to the company, they were repeatedly suppressed.In 1936, the La Follette Committee of the United States Senate investigated and publicized abuses of detective agencies, including Pinkerton.The Pinkerton Agency eventually shifted from detective work to security services, at least in part due to such criticism.