James Hahn, American judge and politician, 40th Mayor of Los Angeles

James Kenneth Hahn is an American lawyer and politician. A Democrat, Hahn was elected the 40th mayor of Los Angeles in 2001. He served until 2005, at which time he was defeated in his bid for re-election. Prior to his term as Mayor, Hahn served in several other capacities for the city of Los Angeles, including deputy city attorney (1975–1979), city controller (1981–1985) and city attorney (1985–2001). Hahn is the only individual in the city's history to have been elected to all three citywide offices. He is currently a sitting judge on the Los Angeles County Superior Court.

The mayor of Los Angeles is the head of the executive branch of the government of Los Angeles and the chief executive of Los Angeles. The office is officially nonpartisan, a change made in the 1909 charter; previously, both the elections and the office were partisan.