Tydings Committee

The Subcommittee on the Investigation of Loyalty of State Department Employees, more commonly referred to as the Tydings Committee, was a subcommittee authorized by S.Res. 231 in February 1950 to look into charges by Joseph R. McCarthy that he had a list of individuals who were known by the Secretary of State to be members of the Communist Party of the United States of America (CPUSA) yet who were still working in the State Department.

The mandate of the committee was to conduct "a full and complete study and investigation as to whether persons who are disloyal to the United States are, or have been, employed by the Department of State." The chairman of the subcommittee was Senator Millard Tydings, a Democrat from Maryland.

On February 20, 1950, McCarthy had delivered a 5-hour speech to the Senate in which he presented the cases of 81 "loyalty risks" who he claimed were working for the State Department. McCarthy declined requests to disclose the actual names of the people on his list, and instead referred to them by "case numbers". It is widely accepted that most of McCarthy's cases were taken from the so-called "Lee list"—a report that had been compiled three years earlier for the House Appropriations Committee. Led by former FBI agent Robert E. Lee, the House investigators had been allowed to review the security clearance documents on State Department employees, and had determined that there were "incidents of inefficiencies" in the security reviews of 108 past and present employees.

The Lee list was also the source of McCarthy's famous list of 57 "cardcarrying Communists" in the State Department. In 1948, the State Department had informed the House that of the 108 cases flagged by Lee, 57 were still working for the department. This list included persons whom Lee had deemed security risks for a variety of reasons, such as marital infidelity or drunkenness, and all of them had been cleared by the State Department's review process.

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