The information about the FBI, its staffing and criminal enforcement efforts, was compiled by TRAC from a variety of sources. The sources included computerized data obtained under the Freedom of Information Act from the Justice Department and from the United States Office of Personnel Management. These data were supplemented by interviews with current and former government officials, attorneys, and agency data processing specialists. Additional information was drawn from internal administrative records and hardcover publications of the Federal Bureau of Investigation; internal administrative records and statistical reports of the Justice Department; electronic databases, internal records and hardcover publications of the Administrative Office of the United States Courts; internal records and published reports of the Office of Personnel Management; electronic databases and report of the U.S. Congress; internal records and published reports of the General Accounting Office; and county-level and geo-based files from the United States Census Bureau, the Federal Deposit Insurance Corporation (FDIC), and the American Medical Association (AMA).