Supreme Court Strikes Down Voter ID Law

The U.S. Supreme Court has ruled that states cannot demand proof of citizenship when people register to vote.

The justices' 7-2 ruling Monday struck down Arizona's requirement that voters prove they are U.S. citizens in order to use a federal registration form. The court's ruling could affect other states with similar laws, including Alabama, Georgia and Kansas. Twelve other states are contemplating similar legislation.

States say the laws were designed to prevent voter fraud, but civil rights groups said the Arizona law was aimed at discouraging certain groups from voting, such as Native Americans, the elderly and minorities.

The ruling only affects those trying to register using federal forms. Most register through the state, meaning they will continue to be asked to provide proof of citizenship when signing up to vote.