A federal judge in Ohio, appointed by President Clinton, has blocked a new state law that would have required voter registration applicants to provide documentary proof of citizenship, such as a passport or birth certificate, before enrolling. Judge Solomon Oliver Jr. ruled on Tuesday that the requirement conflicts with the federal National Voter Registration Act, which bars states from demanding information on driver's licence-linked voter forms that duplicates what the licence application already covers. The ruling touches on the wider US debate over how far states can go in policing non-citizen voting without changes to federal law, and Ohio's Secretary of State has vowed to appeal immediately.

The case, Red Wine & Blue v. Ohio Secretary of State, centred on whether Ohio's House Bill 54 amendment, requiring proof of citizenship for driving licence-linked voter registration, breached the 1993 "Motor Voter Act". Oliver reasoned that since driving licence forms already ask about citizenship, a signed attestation is sufficient and further documentary proof is redundant. Secretary of State Frank LaRose disagreed, citing a case in which an Ohio woman was found not guilty of illegal voting by reason of entrapment after a state motor vehicle clerk wrongly told her she could register, which he says shows attestation alone is inadequate to protect the integrity of elections.