Kathleen M. Williams serves as the Federal Public Defender for the Southern District of Florida, appointed in 1994 by the judges of the Eleventh Circuit Court of Appeals. 

The Office of the Federal Public Defender of the Southern District of Florida was established in 1971, one of the first eight federal defender organizations in the nation. The main office is in Miami, with branch offices in Fort Lauderdale (30 miles north), West Palm Beach (75 miles north), Fort Pierce (125 miles north) and Key West (179 miles south). The Office has an approved staff of 123 employees, including 53 Assistant Federal Public Defenders.

The Federal Public Defender's Office is appointed to represent persons accused of federal criminal law violations, who are unable to retain private counsel. The criminal charges defended are diverse, including drug crimes, tax law violations, firearms offenses, bank robbery, racketeering, bank fraud, environmental crimes, and computer-based offenses. The Office is also appointed to represent clients in extradition, post-conviction and treaty transfer proceedings. Attorneys represent their clients in the U.S. District Court, the U.S. Court of Appeals for the Eleventh Circuit, and the U.S. Supreme Court.