The information about the DEA, its staffing and criminal enforcement efforts, and federal drug enforcement more generally 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 Drug Enforcement Administration; 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 and the U.S. Sentencing Commission; internal records and published reports of the Office of Personnel Management; internal records and published reports of the General Accounting Office, the Congressional Authorization & Budget Submissions as well as Congressional hearings, and reports by the White House Office of National Drug Control Policy. Basic population figures came from the United States Census Bureau..

This section on "About the Data" provides information about the following topics. Choose from the following links for further details on each of these topical areas.

  Data Coverage: what the agency's databases were designed to cover and how these activities were recorded.

  Judging the Quality of Government Data: general information about how to judge the quality of government statistics, and what steps TRAC uses to assess the quality of data it receives.

  Understanding the Terminology which Agencies Use: specialized terminology used by these agency sources in categorizing their activities.