WASHINGTON-- The Supreme Court is diving into state efforts to pare their voting rolls by targeting people who haven't voted in a while.

The justices are hearing argument Wednesday in a case from Republican-led Ohio, one of a handful of states that use voters' inactivity to trigger a process that could lead to their removal from voter rolls. A ruling for Ohio could lead other states to adopt the practice, which generally pits Democrats against Republicans.

Civil rights groups challenging the Ohio process say federal law prohibits using voting inactivity to trigger purges. The federal appeals court in Cincinnati sided with the challengers.

The Trump administration reversed the position taken by the Obama administration and is now backing Ohio's method for pruning its voter rolls.

At the Supreme Court, voting cases often split the court's liberal and conservative justices.

Partisan fights over ballot access are being fought across the country. Democrats have accused Republicans of trying to suppress votes from minorities and poorer people who tend to vote for Democrats. Republicans have argued that they are trying to promote ballot integrity and prevent voter fraud.

Under Ohio rules, registered voters who fail to vote in a two-year period are targeted for eventual removal from registration rolls, even if they haven't moved and remain eligible. The state says it removes names only after local election boards send notices and there's no subsequent voting activity for the next four years. Ohio argues this helps ensure election security.

Backed by 17 other mostly Republican states, Ohio said it is complying with federal law. The state said it only uses the disputed process after first comparing its voter lists with a U.S. postal service list of people who have reported a change of address. But not everyone who moves notifies the post office, the state said.

So the state asks people who haven't voted in two years to confirm their eligibility. If they do, or if they show up to vote over the next four years, voters remain registered. If they do nothing, their names eventually fall off the list of registered voters.

Opponents said the basic problem with what Ohio does is that it purges registered voters who are still eligible to vote.

Civil rights groups contend that a decision for Ohio would have widespread implications because it would fuel a broader effort to make it more difficult and costly to vote. A dozen mainly Democratic states also want the Supreme Court to declare that Ohio's system violates federal law.

A decision in Husted v. A. Philip Randolph Institute, 16-980, is expected by late June.