The four federal judges known to have auditioned for the role of the newest U.S. Supreme Court justice have varying levels of experience deciding health-care cases.

The front-runners appear to be Judge Brett M. Kavanaugh, who has overseen multiple Medicare and Medicaid appeals, and Judge Amy Coney Barrett, a newbie to the federal bench, who doesn’t have any notable health-law decisions on her resume. The two, along with Judge Raymond M. Kethledge and Judge Amul R. Thapar, met with President Donald Trump at the White House July 2. A fifth potential candidate, Sen. Mike Lee (R-Utah), has no judicial experience, but is opposed to abortion and pushed for a full repeal of Obamacare. Two other judges reportedly have talked to Trump about the position, but haven’t been named.

Kethledge and Thapar were on the short list of judges considered by Trump in 2017 to replace the late Justice Antonin Scalia, but Barrett and Kavanaugh are new additions to the 2018 list. Trump’s second Supreme Court pick was made possible by Justice Anthony M. Kennedy’s June 27 retirement from the high court.

This will be a pivotal nomination, as Trump is expected to choose a candidate who is willing to overturn key abortion rulings, rather than someone more in keeping with Kennedy’s moderate position on social issues. In addition to abortion, there are several health-care-related issues bubbling up through the lower courts that could benefit from a justice with a solid background in the area.

The Front-Runner

Kavanaugh, of the U.S. Court of Appeals for the District of Columbia Circuit, is allegedly the front-runner. Some court watchers believe the nominee will be one of the people recently added to Trump’s list, and Kavanaugh has the advantage of having clerked for Kennedy. Moreover, many Supreme Court justices, including Scalia, have been nominated after serving on the D.C. Circuit.

Far-right conservatives have criticized Kavanaugh for saying that the Affordable Care Act complied with the Constitution’s Origination Clause when a finding of noncompliance would have been a basis for invalidating the act. More recently, however, Kavanaugh dissented from a ruling by all the court’s active judges that allowed an unlawful immigrant teenager in U.S. custody to have an abortion. The decision represented “a radical extension of the Supreme Court’s abortion jurisprudence,” Kavanaugh wrote.

Kavanaugh’s position on the D.C. federal appeals court means he has a lot of experience deciding cases involving the Health and Human Services Department, and that experience could bode well for hospitals seeking Supreme Court review of lower court decisions regarding Medicare and Medicaid reimbursement.

For example, Kavanaugh June 29 concurred in a decision that was seen as a big win for hospitals against the Centers for Medicare & Medicaid Services. The court reinstated an administrative appeal in which 277 hospitals claimed a factual error dating back to 1983 that, in the years since, has allegedly reduced the amount of compensation Medicare owed them. Kavanaugh wrote that, while saving money is a good goal, it shouldn’t be done with “phony facts to shift costs onto the backs of hospitals.”

Kavanaugh also ruled against the CMS in a case concerning the way the HHS calculates payments to hospitals that serve a high number of poor and low-income patients, known as disproportionate share hospital (DSH) payments. In 2014, the HHS told Medicare intermediaries to consider Medicare Part C (managed care) patient days as being entitled to Medicare Part A (hospital) benefits, which lowered the hospitals’ DSH reimbursements. The HHS violated the Medicare Act by adopting the policy without giving the public notice and an opportunity to comment, the court said.

The government has asked the Supreme Court to review that decision. Kavanaugh, if nominated and confirmed, would have to sit out the case.

The Controversial Candidate

Barrett appears to be the far-right’s preferred candidate, as she is widely considered to be the most likely potential justice to vote to reverse the high court’s abortion precedent. Although she has very little judicial experience, having taken her seat on the U.S. Court of Appeals for the Seventh Circuit in November 2017, Barrett clerked for Scalia at the Supreme Court and taught law at the University of Notre Dame Law School.

Democrats raised Barrett’s Catholic faith during hearings to confirm her nomination to the Seventh Circuit bench, and likely will bring it up again if she is nominated for the Supreme Court. Senators previously questioned Barrett on whether she could consider sensitive legal issues, like the death penalty and abortion, separately from her religious beliefs. The U.S. Senate Judiciary Committee narrowly confirmed Barrett’s nomination.

Barrett has participated in relatively few Seventh Circuit cases, given her short time on the bench, and none involved health-care issues.

The Former Runner-Up

Trump considered Kethledge, of the U.S. Court of Appeals for the Sixth Circuit, to replace Scalia in 2017, but eventually chose Justice Neil M. Gorsuch. Like Kavanaugh, Kethledge has weighed in on Medicare reimbursement challenges. For example, in 2017, he joined two other judges in upholding HHS reimbursement rate classifications for medical technicians. Kethledge also wrote an opinion saying that Ohio didn’t have to pay for services Medicaid-eligible assisted living patients received before their service plans were finalized.

In other health-care related cases, Kethledge joined an opinion dismissing the appeal of an order requiring arbitration of a dispute involving a nursing home. He also wrote the opinion upholding a Federal Trade Commission order requiring Ohio’s ProMedica Health System Inc. to divest itself of St. Luke’s Hospital prior to a merger—a decision antitrust attorneys predicted would give the FTC the confidence to more closely scrutinize subsequent hospital mergers.

Kethledge also helped derail a $30 million settlement in an antitrust suit against Blue Cross Blue Shield of Michigan. The class members, a group of hospital services purchasers, sued Blue Cross under the Sherman Act for including “most favored nation” clauses in its provider agreements. These clauses allegedly resulted in Blue Cross agreeing to pay hospitals inflated rates if the hospitals would charge even higher rates to other commercial health insurers.

The Trailblazer

Thapar, also of the Sixth Circuit, was the nation’s first South Asian-American judge and a surprise finalist for the U.S. Supreme Court in 2016. In 2018, he could become the first high court justice of South Asian descent.

Thapar spent nine years as a judge on the U.S. District Court for the Eastern District of Kentucky, and Trump elevated him to the appeals court in 2017. Since he joined the Sixth Circuit, the court’s active judges have agreed to rehear a case in which a Planned Parenthood affiliate challenged an Ohio law that prohibited the state health department from paying federal pass-through grants to entities that are associated with health-care providers who perform abortions. A three-judge panel had invalidated the law.

Thapar also agreed with two other Sixth Circuit judges in an unpublished decision that affirmed the dismissal of Michigan doctor’s case against his state licensing board, based on sovereign immunity.

While in the district court, Thapar heard several medical malpractice cases. He also ruled in 2011that a nurse who was fired after using her Facebook page to complain about a hospital’s patient-nurse ratio could pursue her wrongful discharge claim in state court. Thapar said the nurse’s claims weren’t preempted by the National Labor Relations Act or the Labor-Management Relations Act.

The Stealth Candidates

The two other judges Trump is believed to have interviewed are Thomas Hardiman, of the U.S. Court of Appeals for the Third Circuit, and Sixth Circuit Judge Joan Larsen. Hardiman was a finalist for Gorsuch’s seat, which may make him a front-runner this time around.

Larsen had never served on a court before 2015, when she was appointed to the Michigan Supreme Court. She was elected to a full two-year term in November 2016, but Trump elevated Larsen to the Sixth Circuit in 2017. A Scalia clerk, Larsen served as a deputy attorney general in the George W. Bush administration and also was on Trump’s 2017 Supreme Court shortlist.

Bloomberg News reported late July 5 that Trump had narrowed his choice to Kavanaugh, Barrett, and Kethledge.