The American Civil Liberties Union has filed a lawsuit against the state of Georgia on behalf of the Ku Klux Klan, which had tried unsuccessfully to join the state's Adopt-a-Highway program.

The ACLU Foundation of Georgia filed the suit Thursday in Fulton County Superior Court, saying the state violated the group's right to free speech. The suit asks the court to force the state to issue an Adopt-a-Highway permit to the KKK.

The International Keystone Knights of the KKK applied in May to join the "Adopt-A-Highway" program in the north Georgia mountains. Participating groups are recognized with a sign along the road they adopt. State officials said in June they would deny the group's application.

A spokeswoman for Attorney General Sam Olens said Thursday the state hadn't seen the lawsuit.

Tags: lawsuit, ACLU, KKK, Adopt-a-Highway program