Contracts with "Pinkerton Detective Agencies or similar organizations" are prohibited by 5 U.S.C. 3108. This prohibition applies only to contracts with organizations that offer quasi-military armed forces for hire, or with their employees, regardless of the contract’s character. An organization providing guard or protective services does not thereby become a "quasi-military armed force," even though the guards are armed or the organization provides general investigative or detective services. (See 57 Comp. Gen. 524.)