Wikipedia
The Narcotics and Dangerous Drugs Information System, or NADDIS, is a data index and collection system operated by the United States Drug Enforcement Administration (DEA). Comprising millions of DEA reports and records on individuals, NADDIS is a system by which intelligence analysts, investigators and others in law enforcement retrieve reports from the DEA's Investigative Filing and Reporting System (IFRS). NADDIS is thought to have become the most widely used, if least known, tool in drug law enforcement.
The database has been described by DEA as a "pointer index" by which records on millions of individuals, many with no criminal history, can be reviewed quickly to locate complete reports on a subject of interest, their address or phone number.