(Reuters) - Kansas and Arizona filed a lawsuit against the U.S. federal government on Wednesday, seeking court approval for states to require proof of U.S. citizenship when registering to vote.
The lawsuit brought by the two Republican-led states accuses an agency of President Barack Obama's Democratic administration of preventing them from enforcing state laws that require proof of citizenship as a way to prevent illegal immigrants from voting.
The suit, part of an on-going battle over voter registration laws being waged nationwide, demands that the U.S. Election Assistance Commission modify federal voter registration forms to allow states to require proof of citizenship.
The federal form now asks for a verbal pledge that the applicant is a U.S. citizen but does not require documentation as proof.
In June, the U.S. Supreme Court struck down the controversial provision requiring proof of citizenship passed by Arizona voters in a 2004 referendum. The requirement was criticized by immigrant advocacy groups such as the Mexican American Legal Defense and Education Fund.
The groups said it unfairly deterred legal voters from casting ballots because they might not have the required paperwork.
In a 7-2 vote, the nation's highest court said the 1993 National Voter Registration Act trumps the state law approved in the desert state that borders Mexico. The ruling affected Arizona, Kansas, Georgia and Alabama.
But the court left the door open for Arizona to assert its arguments through separate litigation, a possibility mentioned by justices during oral arguments in April.
Supreme Court Justice Antonin Scalia wrote for the majority that Arizona could still challenge the current form in court or ask the commission to include the citizenship requirement on the federal form in the future.
The lawsuit was filed in federal court in Topeka, Kansas, by Arizona Secretary of State Ken Bennett and Kansas Secretary of State Kris Kobach.
Kobach has been active in opposing immigration even before he was elected to state office. As a private lawyer, he was involved in the drafting of the controversial Arizona anti-immigration law passed in 2010 that stirred protests and court challenges.
A number of states led by Republicans have tightened voter identification laws in recent years, prompting criticism from Democrats and some advocacy groups that they will discourage minorities, the elderly and the young from voting.
Republican supporters of the laws said they are aimed at preventing voter fraud.
(Reporting By David Schwartz in Phoenix and David Bailey in Minneapolis; Writing by Greg McCune; Editing by Cynthia Johnston and Ken Wills)