The Georgia chapter of the NAACP has joined with the Georgia Association of Latino Elected Officials to challenge what they say is historic discrimination against minority voters in county commission and school board elections.

The suit, filed Monday in federal court in Atlanta, contends that an at-large election for the county commission chairman and racially gerrymandered districts for other commissioners and school board members have frustrated the will of an increasingly diverse county electorate. Whites voting as a bloc have consistently defeated African-American, Latino and Asian-American candidates, regardless of political party, even though minorities now constitute 53.5 percent of the county population and 42.6 percent of eligible voters, the suit contends.