Sen. Dianne Feinstein of California will be the Judiciary Committee’s new top Democrat in the next Congress, becoming the first woman in that post as the panel plays a critical role vetting Donald Trump’s nominees for the Supreme Court and key Justice Department jobs.

The move comes amid a shakeup Wednesday of Democrats serving as ranking members on Senate committees. Feinstein was next in line for the Judiciary slot after Sen. Patrick J. Leahy of Vermont, the current ranking member, decided to take the top Democratic spot on the Appropriations Committee.

Leahy has served as chairman or ranking member of Judiciary since 2001. He had his choice of three committees where he could serve as ranking member, as the most senior Democrat on the Appropriations, Judiciary and Agriculture committees.

Newly elected Senate Minority Leader Charles E. Schumer told reporters that Feinstein has “huge respect” among Democrats. “She will be a superb ranking member and she’s going to have a very important job making sure that every aspect of the president’s nominees is explored and brought before the public,” the New York senator said.

Feinstein, 83, backed up that sentiment in a written statement about her new role, while pointing out that the Judiciary Committee has been the source of bipartisan solutions on controversial issues such as immigration and sex trafficking.

“When President-elect Trump is willing to support responsible policies and nominees, I’ll hear him out, but this committee has a vital role to protect the Constitution and scrutinize policies, senior officials and judges very carefully, and that’s what we intend to do,” Feinstein said in the statement. “We simply won’t stand aside and watch the tremendous successes achieved over the past eight years be swept away or allow our nation’s most vulnerable populations to be targeted.”

The Judiciary Committee will be at the center of high-profile fights, including the appointment of a new attorney general and a new Supreme Court justice to succeed the late Antonin Scalia, a reliably conservative justice who died Feb. 13. There will be some tension built in since Republicans blocked President Barack Obama’s pick for that spot, Judge Merrick Garland, from March through the end of the year.

[Merrick Garland Trudges On, Awaiting Supreme Court Action]

“After the unprecedented and disrespectful treatment of Merrick Garland — a moderate judge who should have been quickly confirmed — the committee will pay very close attention to proposed nominees to ensure the fundamental constitutional rights of Americans are protected,” Feinstein said.

Feinstein was the first woman to serve on the Judiciary Committee in the wake of the highly contentious confirmation hearings for Justice Clarence Thomas in 1991, which featured Anita Hill’s sexual harassment accusations against Thomas.

The former San Francisco mayor was elected to the Senate in 1992 — dubbed the Year of the Woman because a then-unprecedented four women were elected to the Senate that year. Feinstein is also one of the Democratic Party’s most prominent advocates for gun control and a key voice on policy about the ability of the government’s national security agencies to collect information.

The Californian gave up the ranking member role on the Senate Intelligence Committee to take the Judiciary spot. She will work alongside Sen. Charles E. Grassley of Iowa, who became chairman in 2015 when Republicans took control of the Senate. “We’ve always worked well together,” he said about Feinstein.

Leahy said Feinstein did a great job with the so-called torture report in 2014 focused on the CIA interrogation tactics, which “never would have gotten released if she hadn’t worked so hard.”

“She was under enormous pressure to allow a cover-up. She didn’t. And she’ll do a great job” on Judiciary, he said.

[Feinstein: CIA Spied on Intelligence Committee]

Minnesota Democratic Sen. Amy Klobuchar, the only other woman on the 20-member committee, said Feinstein has been “such a strong voice on issues of judges and security and other things.”

“The committee as a whole has functioned even through really polarized times,” Klobuchar said. “While we’ll have disagreements and there’s some delays, a lot of the delays even on the judge side have tended to be on the floor, not in our committee despite people having very different views.”

“I think that will continue,” Klobuchar said.

Democratic Sen. Chris Coons of Delaware, a Judiciary member, said the committee will play a more central role in the Senate’s work. While the committee could work with the Trump administration on common goals, such as protecting American inventions or working with local law enforcement, Coons noted that Trump “said a number of outrageous things as a candidate.”

“He made proposals that if he tried to enact them would, I think, run up against our core values, our Constitution,” Coons said. “So some of his proposals for banning Muslims from the United States or mass deportations, if carried out to their extreme, would be fought out in the Judiciary Committee.”

Bridget Bowman contributed to this report.