The Arizona Supreme Court unanimously ruled Friday that nearly 98,000 people whose citizenship documents hadn’t been confirmed can vote in state and local races, a significant decision that could influence ballot measures and tight legislative races.

The court’s decision comes after officials uncovered a database error that for two decades mistakenly designated the voters as having access to the full ballot. The voters already were entitled to cast ballots in federal races, including for president and Congress, regardless of how the court ruled.

Secretary of State Adrian Fontes, a Democrat, and Stephen Richer, the Republican Maricopa County recorder, had disagreed on what status the voters should hold. Richer asked the high court to weigh in, saying Fontes ignored state law by advising county officials to let affected voters cast full ballots.

Fontes said not allowing the voters who believed they had satisfied voting requirements access to the full ballot would raise equal protection and due process concerns.

The high court, which leans Republican, agreed with Fontes. It said county officials lack the authority to change the voters’ statuses because those voters registered long ago and had attested under the penalty of law that they are citizens. The justices also said the voters were not at fault for the database error and also mentioned the little time that’s left before the Nov. 5 general election.

“We are unwilling on these facts to disenfranchise voters en masse from participating in state contests,” Chief Justice Ann Scott Timmer wrote in the ruling.

Of the nearly 98,000 affected voters, most of them reside in Maricopa County, which is home to Phoenix, and are longtime state residents who range in age from 45 to 60. About 37% of them are registered Republicans, about 27% are registered Democrats and the rest are independents or affiliated with minor parties.

Arizona is unique among states in that it requires voters to prove their citizenship to participate in local and state races. Voters can demonstrate citizenship by providing a driver’s license or tribal ID number, or they can attach a copy of a birth certificate, passport or naturalization documents.

Arizona considers drivers’ licenses issued after October 1996 to be valid proof of citizenship. However, a system coding error marked nearly 98,000 voters who obtained licenses before 1996 — roughly 2.5% of all registered voters — as full-ballot voters, state officials said.