BISMARCK, N.D. (AP) — Supporters of a proposed ballot measure for congressional age limits in North Dakota are suing to be able to use out-of-state petition circulators to gather signatures.

The initiative’s push comes amid age-related concerns for federal officeholders. U.S. Sen. Dianne Feinstein of California died Thursday at age 90 after facing health issues in recent months. Republican Senate Minority Leader Mitch McConnell, 81, froze twice in front of reporters last summer. Joe Biden, who is the oldest U.S. president ever, is seeking reelection at age 80.

A political scientist says the measure could be an effort to create a test case for the U.S. Supreme Court to see if the court would be willing to allow states to set congressional age limits on an individual basis.

“I assume that’s their goal,” said Mark Jendrysik, professor of political science at the University of North Dakota.

Jared Hendrix, who is leading the effort, said “the people deserve better,” citing a recent instance in which Feinstein appeared confused during a Senate panel’s vote on a major appropriations bill.

“We don’t want these types of issues in North Dakota, so we’re being proactive. I think most people look at the situation and think Senator Feinstein should’ve retired and been at home with her family,” Hendrix said.

Backers of the measure filed the lawsuit Sept. 22 in federal court in North Dakota. Plaintiffs, in addition to the initiative organizers, include the Virginia-based Liberty Initiative Fund and Accelevate 2020, LLC. The former is helping to fund and advance signature-gathering efforts; the latter is a “petition management firm able to deploy petition circulators” who live outside North Dakota, according to the lawsuit’s complaint.

Supporters want to use out-of-state, professional petition circulators to meet the signature goal as “severe winter weather” looms. Measure supporters need to gather more than 31,000 valid signatures of voters by a February deadline to prompt a June 2024 vote.

Under the measure, no one who could turn 81 years old by the end of his or her term could be elected or appointed to the state’s U.S. House or Senate seats.

The lawsuit targets a state constitutional provision that limits petition circulators to North Dakota voters. Out-of-staters who circulate initiative petitions are currently subject to misdemeanor penalties of up to nearly a year’s imprisonment, a $3,000 fine, or both.

Hendrix said the North Dakota law is “discriminatory against ballot measures” because political candidates’ campaigns are allowed to hire out-of-state workers.

The lawsuit names North Dakota Secretary of State Michael Howe and Attorney General Drew Wrigley.

Howe in a statement said, “If you asked them, I’m confident the people of North Dakota would reject the idea that residents of New York, New Jersey, or California can lead efforts to change North Dakota’s most sacred document. The initiated measure process is for the people of North Dakota, by the people of North Dakota.”

Wrigley said his office is evaluating the filing “and will respond as appropriate.”

In 1995, the U.S. Supreme Court ruled that states can’t set qualifications for Congress in addition to those listed in the U.S. Constitution.

Hendrix said, “We can’t speculate on what the courts will do, but they should agree with us.”

Jendrysik said age limits are like term limits in “taking away the ability of the people to elect who they want.”

He cited Feinstein, McConnell and 90-year-old Republican U.S. Sen. Chuck Grassley of Iowa all winning reelection in recent years.

“You already have a remedy for if you believe that these people are too old: vote them out of office,” Jendrysik said.