DES MOINES, Iowa (AP) — Two voter advocacy groups say Iowa must stop rejecting voter ballots from people misidentified as felons.

The Des Moines Register reports that the Brennan Center for Justice and the League of Women Voters of Iowa told Iowa Secretary of State Paul Pate that the rejections violate federal law. An attorney for the Brennan Center says the state could face civil action in federal court if the problems arising from the errant felon database aren’t fixed.

The warnings were contained in a June 13 letter to Pate.

Pate’s staff says he’s working on administrative rule changes that would require courts to provide conviction documents anytime someone is submitted for inclusion on the felon list.

Iowa bars felons from voting unless the governor or president individually restores the right.