Ending a contentious and long-running civil suit that was plagued in recent years with allegations of government attorney misconduct, a federal judge in Washington on Tuesday approved a $3 million settlement and vacated two opinions that the Justice Department said threatened national security.

The suit, filed in 1994 by a Drug Enforcement Administration agent, has dragged on amid disputes about the state secrets privilege. The plaintiff, Richard Horn, alleged then-CIA officer Arthur Brown and Franklin Huddle Jr. of the State Department unlawfully eavesdropped on telephone communication while Horn was stationed in Burma in the 1990s. The suit remained under seal until last year.