Just days after Justice Anthony Kennedy announced his impending retirement from the Supreme Court, Brett Kavanaugh had already made President Donald Trump’s short list to replace him.

Kavanaugh, who Trump made his official nominee Monday night, would fill the court’s empty seat with a reliable conservative attitude, one that just recently ruled in favor of the Trump administration in an abortion case. That finding, as well as his opinions against Obama-era environmental regulations, could put Kavanaugh, 53, in the hot seat with Democrats during the confirmation process.

But as a member of Federalist Society and textualist similar to the late Justice Antonin Scalia, Kavanaugh will likely transform Kennedy’s swing vote in the exact ways Trump and conservatives hope.

"I believe that an independent judiciary is the crown jewel of our Constitutional republic," Kavanaugh said after Trump's announcement Monday night. "If confirmed by the Senate, I will keep an open mind in every case. And I will always strive to preserve the Constitution of the United States and the American rule of law."

A Starr lawyer

After graduating from Yale Law School, Kavanaugh clerked for the very justice he’s now attempting to replace on the Supreme Court from 1994 to 1997. And he briefly worked in the office alongside Neil Gorsuch, Trump’s previous Supreme Court appointee.

Once he left Kennedy’s side, Kavanaugh stepped onto the Starr Investigation, which attempted to chronicle various abuses of power within the Clinton White House, including the suicide of White House aide Vince Foster. Kavanaugh led that specific arm of the investigation and later wrote much of the Starr report as a whole, which included graphic details of Clinton’s relationship with Monica Lewinsky.

Following the Starr report, Kavanaugh’s time working alongside presidents wasn’t over: He served as one of George W. Bush’s lawyers during the Florida recount and later, one of his close aides for several years. Then in 2003, Bush nominated Kavanaugh to the U.S. Court of Appeals for the District of Columbia Circuit, a bench that’s launched several of its member to the high court.

Democrats, however, worried he was overly partisan and stalled his nomination for three years before he eventually took the bench. In the 12 years since, Kavanaugh has solidified his record as a reliable conservative on issues from regulating the environment to prioritizing religious freedom.

Where he stands on abortion

President Trump campaigned on the promise of overturning Roe v. Wade, the landmark 1973 case that gave women a constitutional right to choose an abortion. During his first chance to replace a Supreme Court justice, he also said he’d only appoint someone who’d carry out those wishes.

Kavanaugh's record on abortion, however, isn’t as clear-cut as the pro-life right had hoped, especially given his background as a devout Catholic.

When the ACLU sued the Trump administration last year for preventing an undocumented teenager from seeking an abortion while in federal custody, the case came before Kavanaugh’s court. As a majority, the D.C. circuit ruled that the government had to allow the teenager to get the abortion immediately. But Kavanaugh dissented — although with less extreme reasoning than some of his colleagues.

Kavanaugh didn’t believe the Trump administration had to let the teen get the abortion immediately. “The government has permissible interests in favoring fetal life, protecting the best interests of a minor, and refraining from facilitating abortion,” he wrote. But rather than following in the footsteps of one of his colleagues — who argued that undocumented immigrants don’t have constitutional rights — he chiefly wanted the government to have more time to find the teen a sponsor, who could take the teen out of federal custody.

In 2015, Kavanaugh’s court also struck down an Obama-era mandate that required religious organizations to give their employees access to contraception. In his dissent, he wrote that the mandate “substantially burdens” the ability of religious organizations to exercise their own religion because of the monetary cost of providing contraception.

In general, Kavanaugh tends to uphold religious freedoms in the face of constitutional issues. Just this March, the D.C. Metro vetoed an ad the Catholic Archdiocese of Washington wanted to run, which featured the slogan, “find the perfect gift,” with images of shepherds following a star. The Archdiocese sued the Metro for violating its First Amendment rights, and during the case, Kavanaugh called the ad ban “pure discrimination” and “odious to the Constitution.”

Environmental impact

Because the D.C. circuit largely handles administrative decisions, the vast majority of Kavanaugh’s opinions logically fall within that scope, including several regarding the Environmental Protection Agency. He’s especially skeptical of the federal government’s power to regulate business, although he hasn’t always ruled against the EPA.

During the same year, he dissented on a decision not to rehear a case that would allow the EPA to disregard any cost-benefit analysis when considering how to deal with air pollution. The Supreme Court later reversed that decision, citing Kavanaugh’s dissenting opinion, according to the Heritage Foundation.

Kavanaugh also struck down an Obama-era administration regulation on hydrofluorocarbons, or HFCs, in 2017. “Climate change is not a blank check for the President,” he wrote for the majority.

But Kavanaugh’s decision haven’t always roadblocked the Obama administration: He ruled in 2011 that the Affordable Care Act was constitutional, leading the way for Obamacare to go into effect.

So far, the Trump White House has tried, and succeeded, to rollback dozens of environmental regulations. But some still remain entangled in the lower courts and could even hit the Supreme Court — maybe with Kavanaugh on the bench.

The future

Come fall, Kavanaugh could hear any of the 38 cases the Supreme Court already decided to hear in the upcoming term. But that’s only if he can endure what’s fated to be a contentious confirmation process.

Mirroring Republicans’ tactics that ultimately blocked President Obama’s Supreme Court nominee from taking the bench, Democrats could rally to postpone Kavanaugh’s confirmation hearing until after midterms. Even then, the party would need to convince every one of its members in the Senate and at least two Republicans to vote against Kavanaugh to prevent him from securing a seat on the high court.

So far, none of next term’s cases deal with legalizing abortion or religious freedom, two areas of concern for liberals worried about the court without Kennedy’s swing vote. But the justices do plan to hear a case that pits the scope of Endangered Species Act against private land owners’ rights, Weyerhaeuser v. US Fish and Wildlife Service.

Kavanaugh had also argued that presidents shouldn’t have to deal with civil lawsuits, criminal investigations, or questions from prosecutors or defense attorneys while in office. That’s led some of his critics to question how he would respond if special counsel Robert Mueller’s investigation into Russia’s interference in the 2016 campaign landed in the Supreme Court.

Clarification__: Due to editor's error, a previous version of this story noted that Democrats called Kavanaugh an "extremist" judge during his confirmation to the U.S. Court of Appeals for the District of Columbia Circuit. That characterization applied to a number of judges, not just Kavanaugh. The story has been updated.