PROVIDENCE, R.I. (WPRI) — Democratic U.S. Sen. Sheldon Whitehouse has caused a major stir in Washington with a U.S. Supreme Court filing that warns the justices they could face political consequences depending on how they handle an upcoming gun case.

The case, New York State Rifle & Pistol Association v. City of New York, challenges a regulation that New York City leaders put in place regarding the transporting of handguns. Earlier this year the justices agreed to review whether lower-court judges were correct to rule the New York regulation did not violate the Second Amendment.

In the Aug. 12 amicus brief, Whitehouse and four other Democratic senators suggested the court’s conservative justices were doing the bidding of the National Rifle Association and the Federalist Society by taking up the case. They also highlighted a recent Quinnipiac poll that found 51% of Americans say the “Supreme Court should be restructured in order to reduce the influence of politics.”

“The Supreme Court is not well. And the people know it,” the senators wrote, citing the poll. “Perhaps the Court can heal itself before the public demands it be ‘restructured in order to reduce the influence of politics.’ Particularly on the urgent issue of gun control, a nation desperately needs it to heal.”

The brief — which The Washington Post described as “incendiary” — didn’t sit well with conservatives. The Wall Street Journal’s influential editorial page labeled it as “an enemy-of-the-court brief,” and National Review’s David French called it “easily the most malicious Supreme Court brief I’ve ever seen.”

“When you hear Democrats talking about expanding the Supreme Court……..they are talking about making the Court more liberal,” Senate Judiciary Committee Chairman Lindsey Graham, R-South Carolina, tweeted. “This has been a Dream of the Left for decades. I will do everything in my power to ensure that dream is NEVER fulfilled!”

Whitehouse defended the brief in a post on Medium, saying he took pride in the fact that “the far right” was “freaking out.”

“Anything that might unhinge their decades-long campaign to capture the Court unhinges them as well,” he wrote. “The last time they got this freaked out was when I suggested that DOJ should investigate whether the fossil fuel industry was lying about climate change as culpably as the tobacco industry lied about the dangers of its product (DOJ won that tobacco case, btw).”

“We think this fight over the independence of our courts is one well worth having,” he added.

The polling firm Rasmussen released a survey Monday that showed 43% of American likely voters agreed with the senators’ assertion that the court “is not well” and may need to be “restructured,” while 34% disagreed and 23% weren’t sure. The poll included 1,000 likely voters who were surveyed by phone and online.

Meanwhile, the conservative advocacy group Judicial Watch said Monday it has filed a complaint against Whitehouse with the Rhode Island Supreme Court for alleged unauthorized practice of law, citing his status as an inactive member of the Rhode Island bar. Whitehouse’s office counters that he is a member of the U.S. Supreme Court bar. (He was admitted in 1986.)

Joining Whitehouse on the court filing were fellow Democratic senators Mazie Hirono of Hawaii, Richard Blumenthal of Connecticut, Richard Durbin of Illinois and Kirsten Gillibrand of New York. All but Gillibrand serve with Whitehouse on the Senate Judiciary Committee.

Ted Nesi (tnesi@wpri.com) is WPRI 12’s politics and business editor and a Target 12 investigative reporter. He is a weekly panelist on Newsmakers and hosts Executive Suite. Follow him on Twitter and Facebook