With about six months left until his term in the White House expires, President Joe Biden isn't shying away from taking on a tough challenge, unveiling his long-awaited proposals to reform the Supreme Court on Monday, calling for a binding code of conduct and term limits for justices on the high bench.

The Democratic president also urged lawmakers to pass a constitutional amendment that would limit presidential immunity following the high court's ruling earlier this month shielding presidents from criminal prosecution for official acts.

"I share our founders' belief that a president must answer to the law. That a president is accountable when he exercises the great power of the presidency. We're a nation of laws, not kings and dictators," Biden said in remarks at the Lyndon Baines Johnson Library and Museum in Austin to commemorate the 60th anniversary of the Civil Rights Act.

During arguments in the case, Trump v. United States, conservative Justice Neil Gorsuch categorized the weight of their decision would be "writing a rule for the ages."

Biden on Monday disagreed: "That isn't true. The court made a ruling for one, the former president. No other president in our history has asked for this kind of immunity for criminal actions, and no president, no former president, not me, not one, not one, should have been given an exception to this with such immunity.

In an op-ed for The Washington Post, which was published earlier Monday, Biden invoked the nation's founding principles when it came to his proposed amendment. 

"This nation was founded on a simple yet profound principle: No one is above the law. Not the president of the United States," Biden wrote. "Not a justice on the Supreme Court of the United States. No one."

"But the Supreme Court’s 6-3 decision on July 1 to grant presidents broad immunity from prosecution for crimes they commit in office means there are virtually no limits on what a president can do. The only limits will be those that are self-imposed by the person occupying the Oval Office," he continued. "If a future president incites a violent mob to storm the Capitol and stop the peaceful transfer of power — like we saw on Jan. 6, 2021 — there may be no legal consequences. And that’s only the beginning."

Biden, in his proposal, specifically calls for:

• Term limits: Biden supports a Congress passing legislation allowing a president every two years to appoint a justice to serve an 18-year term in active service on the court
• A binding code of conduct: The president urged Congress to enact a "binding, enforceable conduct and ethics rules" that mandate a justice disclose gifts, refrain from outward political activity and recuse themselves when they or a spouse have conflicts of interest, financial or otherwise
• Immunity amendment: Biden called for lawmakers to pass the No One Is Above the Law Amendment, which would say that the U.S. Constitution does not shield a president ffrom immunity for criminal activity

"I served as a U.S. senator for 36 years, including as chairman and ranking member of the Judiciary Committee. I have overseen more Supreme Court nominations as senator, vice president and president than anyone living today. I have great respect for our institutions and the separation of powers," Biden wrote in his op-ed. "What is happening now is not normal, and it undermines the public’s confidence in the court’s decisions, including those impacting personal freedoms. We now stand in a breach."

While unlikely to be passed into law, given Democrats' narrow majority of the U.S. Senate and Republican control of the House of Representatives, it will no doubt serve to highlight the stakes of November's election with 99 days to go until Election Day — and put the Supreme Court and its 6-3 conservative majority in the spotlight.

Former President Donald Trump nominated three justices to the federal bench during his sole White House term, including Justice Neil Gorsuch, who filled a vacancy that opened up during the Obama administration that Senate Republicans refused to allow the Democratic president to fill, and Justice Amy Coney Barrett, who replaced liberal Justice Ruth Bader Ginsburg just weeks before the 2020 presidential election.

The high court's conservative majority issued opinions that greatly expanded gun rights, overturned major decisions on federal regulatory powers, and, arguably most notably, reversed the landmark ruling that guaranteed the nationwide right to an abortion in 2022. 

Biden's proposed changes also come amid outcry from Democrats and ethics watchdogs about scandals involving some of the court's members. Justice Clarence Thomas faced scrutiny after failing to disclose luxury trips from a Republican megadonor, while fellow conservative Justice Samuel Alito rebuffed calls to recuse himself from cases involving Trump and Jan. 6 defendants after it was revealed that flags associated with efforts to overturn the 2020 presidential election flew over his homes.   

The plan comes a little more than a week after Biden announced he would not run for reelection and endorsed Vice President Kamala Harris to take his place at the top of the Democratic ticket.

Harris backed Biden's call for reform, saying that they both "believe that the American people must have confidence in the Supreme Court."

"Yet today, there is a clear crisis of confidence facing the Supreme Court as its fairness has been called into question after numerous ethics scandals and decision after decision overturning long-standing precedent," Harris said.

"These popular reforms will help to restore confidence in the Court, strengthen our democracy, and ensure no one is above the law," she added.

Other Democrats cheered Biden's proposals, while Republicans lambasted it as a power grab.

"Over the last few years, we have witnessed our freedoms recede and presidential powers dramatically expand through the actions of a Supreme Court willing to cast aside all precedent in favor of its reactionary agenda," said California Rep. Adam Schiff, a candidate for U.S. Senate. "It is essential that we take strong action to restore balance and accountability to the highest court in the land."

“Nearly 250 years ago, our founders created a constitutional order in which presidents were not kings, and our nation would be bound by the rule of law. As this partisan and runaway Supreme Court drags us further from these fundamental, foundational principles, the need for reform has never been greater," he added.

Illinois Sen. Dick Durbin, the chairman of the Senate Judiciary Committee, pointed out that his panel "has verified and reported lavish trips by sitting justices that were paid for by wealthy benefactors, including some previously unknown to the public."

“These episodes call into question the ability of justices to remain fair and impartial when these parties have interests before the Court," Durbin continued. "For instance, Justice Thomas’s spouse was on the payroll of political organizations seeking to overturn the 2020 election, yet Justice Thomas refused to recuse himself from cases on issues directly related to the January 6th insurrection. That includes the Supreme Court’s presidential immunity decision, which was wrongly decided and must be remedied.

“If Chief Justice Roberts won’t use his existing authority to implement reform, Congress should use its established Constitutional authority to require the Court to implement ethics reforms consistent with every other federal court. The American people are demanding Supreme Court ethics reform, and I will continue my twelve-year effort until it is done," the Illinois Democrat added.

But House Speaker Mike Johnson charged that Biden's proposal "would tilt the balance of power and erode not only the rule of law, but the American people’s faith in our system of justice."

"This proposal is the logical conclusion to the Biden-Harris Administration and Congressional Democrats’ ongoing efforts to delegitimize the Supreme Court," the Louisiana Republican said, adding: "It is telling that Democrats want to change the system that has guided our nation since its founding simply because they disagree with some of the Court’s recent decisions. This dangerous gambit of the Biden-Harris Administration is dead on arrival in the House.”

In his remarks later Monday, Biden said of Johnson, "I think his thinking is dead on arrival," to cheers and applause.

Trump, the Republican presidential nominee, has accused Biden and Democrats of attempting to "Play the Ref" with such reforms.

“The Democrats are attempting to interfere in the Presidential Election, and destroy our Justice System, by attacking their Political Opponent, ME, and our Honorable Supreme Court," Trump wrote on his Truth Social platform earlier this month. "We have to fight for our Fair and Independent Courts, and protect our Country."

Biden's proposed reforms notably do not call for an expansion of the court, which some Democrats have called for in the wake of Trump's reshaping of the bench, but the Democratic president has expressed skepticism about.