The push to reform the U.S. Supreme Court got a significant boost Wednesday as the Congressional Progressive Caucus voted to officially endorse the Judiciary Act of 2021, which would add four seats to the bench and restore balance to what critics call a “hyperpartisan 6-3 stolen court.”

Rep. Pramila Jayapal (D-Wash.), who chairs the caucus, announced that following a number of rulings in the past several years attacking reproductive rights, voting rights, and other key tenets of a healthy democracy, its members have “determined that the urgent work to restore American democracy must include expanding the Supreme Court.”

“The current bench was filled by a partisan, right-wing effort to entrench a radical, anti-democratic faction and erode human rights that have been won over decades,” Jayapal said in a statement Wednesday. “As a co-equal governing body, Congress cannot sit by while this attack on the Constitution continues unchecked. I am proud that our caucus is joining the fight to expand the court and restore balance to the bench.”

“The current bench was filled by a partisan, right-wing effort to entrench a radical, anti-democratic faction and erode human rights that have been won over decades.”

The official endorsement of the Judiciary Act—proposed in the House by Reps. Jerrold Nadler (D-N.Y.), Hank Johnson (D-Ga.), and Mondaire Jones (D-N.Y.) and in the Senate by Sen. Ed Markey (D-Mass.)—comes four months after the Supreme Court outraged reproductive rights advocates when it allowed Senate Bill 8, Texas’ extreme forced-pregnancy law, to go into effect.

The court is dominated by six right-wing justices, three of whom were appointed by former President Donald Trump. Republican leader Sen. Mitch McConnell (R-Ky.) refused to hold a vote on former President Barack Obama’s nominee and then reformed the legislative filibuster to push through Trump’s nominations—a maneuver he is now claiming would be a show of “genuine radicalism” if used by the Democrats.

With a conservative majority, the high court in recent years has gutted the Voting Rights Act of 1965, eliminating a provision that prevented discriminatory voting laws; weakened labor unions by ruling that public sector bargaining units cannot collect fees from all workers; and upheld Trump’s travel ban targeting people from majority-Muslim countries.

Such rulings have destroyed the court’s “own legitimacy,” said Johnson, and have upended “decades of precedent and progress in this nation.”

“Unless we take action, the court’s assault on our democracy and our fundamental freedoms will only get worse,” said Jones. “But we are not powerless to stop these attacks.”

The CPC’s endorsement shows that progressives in Congress “understands that this Supreme Court threatens the democratic foundations of our nation,” said Sen. Elizabeth Warren (D-Mass.), who announced her support for court expansion last month.

Advocacy groups including Demand Justice, Stand Up America, and Take Back the Court have argued that the Supreme Court has been expanded in the past—contrary to Republicans’ claims that the Judiciary Act of 2021 is somehow “radical.”

“Congress has actually changed the Supreme Court’s size seven times through legislation, previously having set the number of justices on the Court to as few as five and as many as 10,” Take Back the Court’s website notes. “And of course, it had only eight justices for a time when Senate Republicans violated all historical norms to hold the late Justice Antonin Scalia’s seat open until it could be filled by a Republican president.”

The CPC’s endorsement shows “more and more Democrats understand it is the only way to restore balance to the Supreme Court,” said Brian Fallon,  executive director of Demand Justice.

“With this endorsement, the CPC is giving a major boost to the only reform bold enough to rebalance a Supreme Court that currently threatens any progress on issues progressives care about,” Fallon said.

The Judiciary Act has more than 50 co-sponsors as well as the support of the CPC and dozens of civil society groups, bringing the country “closer than ever to restoring balance to the nation’s highest court and building a judiciary, and a democracy, that work for everyone,” Jones said.