summary report. The first investigative reports submitted in response to this request were delivered to the Commission on December 20, 1963. On December 18, the Secret Service submitted a detailed report on security precautions taken before President Kennedy's trip to Texas and a summary of the events of November 22, as witnessed by Secret Service agents. A few days later the Department of State submitted a report relating to Oswald's defection to the Soviet Union in 1959, and his return to the United States in 1962. On January 7 and 11, 1964, the attorney general of Texas submitted an extensive set of investigative materials, largely Dallas police reports, on the assassination of President Kennedy and the killing of Oswald.

As these investigative reports were received, the staff began analyzing and summarizing them. The members of the legal staff, divided into teams, proceeded to organize the facts revealed by these investigations, determine the issues, sort out the unresolved problems, and recommend additional investigation by the Commission. Simultaneously, to insure that no relevant information would be overlooked, the Commission directed requests to the 10 major departments of the Federal Government, 14 of its independent agencies or commissions, and 4 congressional committees for all information relating to the assassination or the background and activities of Lee Harvey Oswald and Jack Ruby.

After reviewing the accumulating materials, the Commission directed numerous additional requests to Federal and State investigative agencies. The Federal Bureau of Investigation and the Secret Service executed the detailed requests for statements of witnesses and examinations of physical evidence with dispatch and thoroughness. All these reports were reviewed and analyzed by the Commission. Additional investigative requests, where appropriate, were handled by Internal Revenue Service, Department of State, and the military intelligence agencies with comparable skill. Investigative analyses of particular significance and sensitivity in the foreign areas were contributed by the Central Intelligence Agency. On occasion the Commission used independent experts from State and city governments to supplement or verify information. During the investigation the Commission on several occasions visited the scene of the assassination and other places in the Dallas area pertinent to the inquiry.

The scope and detail of the investigative effort by the Federal and State agencies are suggested in part by statistics from the Federal Bureau of Investigation and the Secret Service. Immediately after the assassination more than 80 additional FBI personnel were transferred to the Dallas office on a temporary basis to assist in the investigation. Beginning November 22, 1963, the Federal Bureau of Investigation conducted approximately 25,000 interviews and reinterviews of persons having information of possible relevance to the investigation and by September 11, 1964, submitted over 2,300 reports totaling approximately 25,400 pages to the Commission. During the same period the Secret Service conducted approximately 1, 550 interviews and submitted 800 reports totaling some 4,600 pages.