In just a matter of months before midterms and weeks before mail-in ballots are set to go out, a new federal rule is allowing the United States Postal Service to intercept and reject some mail-in ballots.

Some voting rights groups in New York, including Common Cause New York and The League of Women Voters, are suing to keep it from being implemented.

“Leaders can’t change the rules this close to an election, and they shouldn’t be changing the rules simply to hold on to power,” said Susan Lerner, executive director of Common Cause New York.

“We’re really seeing this ruling by the USPS really as an overstep,” said Erica Smitka, executive director of The League of Women Voters. “Our states run our elections.”

The state of New York is also suing.

Attorney General Letitia James has joined a coalition of 23 other Democratic attorneys general and the governor of Pennsylvania in taking the U.S. Postal Service to court.

It’s to stop the rule, which was finalized at President Doanld Trump’s direction and forces states to hand over lists of every eligible mail voter to the postal service and requires pre-approval of ballot envelope designs.

Any voter missing from the federal list, or using an envelope the postal service hasn’t approved, could be rejected and not delivered, even if that voter is fully eligible and registered to vote under state law.

In a statement, James said in part: “The USPS has no authority to decide who can and cannot vote by mail. This new policy will just create confusion, unnecessary costs, and unacceptable risks for voters going into Election Day.”

The finalization of the new rule follows the U.S. Supreme Court on Monday staying a lower court’s ruling which directed USPS to officially announce this rule.

The Legal Defense Fund talks about the legality of this rule.

“I want to be absolutely clear that the president has very little power over elections,” said John Cusick, assistant counsel with the Legal Defense Fund. “He simply cannot do this. That’s why it’s so important for us to continue to push back to make sure the fight and the facts are right.”

Spectrum News 1 reached out to USPS for comment and did not hear immediately back.

Voting rights groups are encouraging voters to make a plan for Election Day, and to know voting deadlines. Also, if you’re planning on voting by mail to request a ballot early from your board of elections.