From its first meeting on December 5, 1963, the Commission viewed the Executive order as an unequivocal Presidential mandate to conduct a thorough and independent investigation. Because of the numerous rumors and theories, the Commission concluded that the public interest in insuring that the truth was ascertained could not be met by merely accepting the reports or the analyses of Federal or State agencies. Not only were the premises and conclusions of those reports critically reassessed, but all assertions or rumors relating to a possible conspiracy, or the complicity of others than Oswald, which have come to the attention of the Commission, were investigated. On December 13, 1963, Congress enacted Senate Joint Resolution 137 (Public Law 88-202)[F-3] empowering the Commission to issue subpoenas requiring the testimony of witnesses and the production of evidence relating to any matter under its investigation. In addition, the resolution authorized the Commission to compel testimony from witnesses claiming the privilege against self-incrimination under the fifth amendment to the U.S. Constitution by providing for the grant of immunity to persons testifying under such compulsion. Immunity under these provisions was not granted to any witness during the Commission’s investigation. The Commission took steps immediately to obtain the necessary staff to fulfill its assignment. J. Lee Rankin, former Solicitor General of the United States, was sworn in as general counsel for the Commission on December 16, 1963. Additional members of the legal staff were selected during the next few weeks. The Commission has been aided by 14 assistant counsel with high professional qualifications, selected by it from widely separated parts of the United States. This staff undertook the work of the Commission with a wealth of legal and investigative experience and a total dedication to the determination of the truth. The Commission has been assisted also by highly qualified personnel from several Federal agencies, assigned to the Commission at its request. This group included lawyers from the Department of Justice, agents of the Internal Revenue Service, a senior historian from the Department of Defense, an editor from the Department of State, and secretarial and administrative staff supplied by the General Services Administration and other agencies.