Ketanji Brown Jackson Won’t Be Able to Change a Radical Court. Yet.

It took 233 years, but the United States Supreme Court is finally on the cusp of getting its first Black female justice.

President Biden’s nomination of Ketanji Brown Jackson, a federal appeals court judge who would replace the retiring Justice Stephen Breyer, is a follow-through on Mr. Biden’s campaign promise to open up the court’s membership in a way none of his predecessors did.

“For too long, our government, our courts haven’t looked like America,” Mr. Biden said in announcing Judge Jackson’s nomination. “I believe it is time that we have a court that reflects the full talents and greatness of our nation.”

Judge Jackson’s nomination is cause for celebration. It is a well-deserved acknowledgment of her years of experience and her qualifications for the job, not to mention a symbol of American progress and a redefinition of who is entrusted with the awesome power to decide the meaning of our Constitution and laws.

It is heartening that the composition of the Supreme Court has begun to reflect the diversity of the nation. White men make up less than one-third of the U.S. population but have accounted for 94 percent of Supreme Court justices.

Yet while the court will now look a little more like the nation, the ideology of its current six-member majority is far to the right of the average American. And the willingness of those justices in the majority to overturn both federal laws and the court’s own precedents — on everything from abortion rights to voting rights to affirmative action to labor unions and more — suggests that the court’s public standing, already at record low levels, will continue to decline.

If she is confirmed, Judge Jackson will bring vital, underrepresented experiences and intellectual firepower to the high court.

Born in the nation’s capital and raised in Florida, she is a graduate of both Harvard University and its law school. After clerking for the justice she is now poised to replace, she worked at a private law firm and then as a federal public defender. That role is central to the nation’s justice system, and yet no previous justice has been a public defender. Combined with Judge Jackson’s work on the United States Sentencing Commission, that promises to bring informed and nuanced insights to the complex criminal justice policy issues that led to the nation’s four-decade prison boom. She has a decade’s worth of judicial experience to draw on as well: first as a trial judge on the district court in Washington, D.C. — a post for which the Senate unanimously confirmed her — and then on the Court of Appeals for the D.C. Circuit, to which Mr. Biden appointed her last year.

In short, she is as prepared as any of the sitting justices, and perhaps more than some, to assume the role of a final arbiter of the nation’s most pressing legal disputes.

The current court — whose conservative supermajority was manufactured over the past several years in a series of power grabs by Senator Mitch McConnell and his Republican caucus — is now the most right-wing it has been in a century, even as the country as a whole has moved left. Judge Jackson can’t arrest that hard right turn alone, but when she finds herself in dissent, she can speak out loud and clear, not only to her fellow justices but also to the American people, in order to help them understand how far out of sync the court is with the country. Dissents don’t make law, but they can point the way to a better future, as Justice John Marshall Harlan did with his powerful solo dissent from one of the court’s most egregious rulings, Plessy v. Ferguson, in 1896.

More than a century later, the Supreme Court finds itself in a precarious position; a record low 40 percent of Americans approve of its work, according to Gallup. Justice Breyer has long been sensitive to the risks of a politicized court, and he went to great lengths to persuade the public not to think about the Supreme Court in a partisan way. He insisted that all justices leave their politics at the door when they put on their robes.

True judicial independence may be hard to achieve, but it is vital. As Alexander Hamilton pointed out, the courts have the power of neither the sword nor the purse. Their ability to issue life-altering rulings derives entirely from the public’s acceptance of their legitimacy. That acceptance depends, in turn, on the sense that the courts are doing their best to remain fair and impartial, despite the swirl of politics and partisanship around them. The moment people stop believing this, the courts’ legitimacy is destroyed.

The collapse in confidence in the high court has grave implications for American government and society. Yet this is the only Supreme Court we have. What can be done to begin to repair its standing?

The first step is personnel: appointing justices who will interpret the Constitution as a document that can adapt to changing circumstances and that embodies the nation’s highest and most enduring ideals. For now, justices like that are in the minority. But the power of dissent is real and can lay the groundwork for future courts and the American people.

One reform that could be achieved in the near future would be to apply to the justices the same code of ethical conduct that applies to all lower federal court judges, prohibiting the sorts of political activities that can create the appearance of bias. Recent revelations about the political activism of Justice Clarence Thomas’s wife put that issue front and center. But it is relatively small potatoes in the larger picture of the court’s role in American life and politics.

The reforms that would have a far more meaningful impact are the hard ones. The most obvious to consider is term limits, which have enjoyed consistent support from both conservatives and liberals. Steven Calabresi, a co-founder of the Federalist Society, wrote in The Times that lifetime appointments created a “self-perpetuating oligarchy” and that carefully timed retirements only contributed to the public perception of justices as political actors. The strongest proposal involves staggered 18-year terms for justices, giving every president at least two and as many as four appointments. There are ways to do this without amending the Constitution, but it would not be easy.

Even if term limits could be set tomorrow, they would not by themselves reduce the court’s outsize power in American life. This power has only grown as Congress has ceded its lawmaking authority, funneling the most important debates and decisions about a democracy of more than 330 million people to a panel of nine justices.

There is a deeper lesson here, which is that reforming the Supreme Court is necessary but it is also insufficient. No matter who sits on the bench, the most important and lasting progress toward a fairer and more equal nation will be won outside the court, not within it.

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