Wichita ? Voting rights groups filed an appeal Friday of a judge’s order that federal election officials must help Kansas and Arizona enforce state laws requiring new voters to provide documentation proving their U.S. citizenship.

A court filing sent to the 10th U.S. Circuit Court of Appeals challenges a ruling earlier this month by U.S. District Judge Eric Melgren in Wichita. Melgren had ordered the U.S. Election Assistance Commission to immediately modify a national voter registration form to add special instructions requiring proof of citizenship for Kansas and Arizona residents.

The appeal was filed by more than a dozen voting rights groups and individuals who had earlier intervened in the case on behalf of the election commission. They include the League of Women Voters of the United States, Project Vote Inc., Inter Tribal Council of Arizona, Common Cause, Arizona Advocacy Network, League of United Latin American Citizens Arizona, Southwest Voter Registration Education Project, Chicanos Por La Causa and others.

While the documents filed Friday do not specify the grounds for the appeal, the national president of the League of Women Voters, Elisabeth MacNamara, said the U.S. Supreme Court has already found that the National Voter Registration Act pre-empts state law requiring documentary proof of citizenship, and that Melgren’s ruling is contrary to the Supreme Court decision handed down last year.

“What we believe the judge got it wrong and the judge did not follow the roadmap set out by the Supreme Court in making this decision,” MacNamara said.

The EAC had previously rejected the states’ requests for the stiffer documentation requirements, finding that the added documentation results in an overall decrease in registration of eligible citizens — undermining the core purpose of the National Voter Registration Act.

Kansas Secretary of State Kris Kobach, who brought the lawsuit, did not immediately respond to a message seeking comment.

Both Kansas and Arizona require people registering to vote to provide a birth certificate, passport or other documentation proving their U.S. citizenship. The federal registration form simply requires prospective voters to sign a statement, under penalty of perjury, declaring they are citizens.

Kobach has championed his state’s proof-of-citizenship law as a way to prevent noncitizens from voting, particularly those in the U.S. illegally. Critics say incidents of non-citizens voting are extremely rare, and that such Republican-backed proof-of-citizenship laws hurt voter registration efforts and disenfranchise voters from certain groups that tend to vote Democrat, such as minorities and college students.

Kobach and Arizona Secretary of State Ken Bennett, both conservative Republicans, sued the agency last year seeking the state-specific rules on the national form for their residents.

The Justice Department, which represents the EAC, has argued that changing the requirements for those two states would in essence affect nationwide policy, because it might encourage other states to seek increased proof of citizenship to register to vote in federal elections.