Sen. Mike Lee locked horns with TV host George Stephanopolous early Sunday over President Donald Trump’s nomination of Judge Amy Coney Barrett to the Supreme Court.

Lee was a guest on ABC’s “This Week with George Stephanopolous,” where he hailed Barrett’s nomination, saying he hoped it would lead to the court declaring the Affordable Care Act unconstitutional. The court is set to hear oral arguments on the latest case challenging the law just days after the 2020 election.

“I believe the Affordable Care Act was unconstitutional when it was enacted. It was unconstitutional when it was litigated in 2012. The fact that Congress chose to enact an unconstitutional law shouldn’t tarnish Judge Barrett in this. Her job is to figure out whether it’s unconstitutional or not,” Lee said.

If the court strikes down the law, experts say millions of Americans could lose their health insurance, especially those with preexisting conditions, unless Congress quickly passed a new plan.

Lee sits on the Senate Judiciary Committee, which will conduct confirmation hearings for Barrett beginning Oct. 12.

Stephanopolous pressed Lee on whether Barrett should recuse herself from any potential case litigating the outcome of the 2020 presidential election, since she was nominated by Trump so close to Election Day. Trump has warned of a “4-4 tie” in case of an election dispute, which is one of the reasons he has moved so quickly to fill the seat left vacant by the late Justice Ruth Bader Ginsburg.

“You have no problem with the idea that a president nominating someone 38 days before an election would then have that person sit in judgment of the very election in play?” asked Stephanopolous.

“It’s not wrong for the president to point out that it might be a good thing to have a court that’s fully impaneled. That’s not an unreasonable, untenable position to make,” Lee responded. “Judge Barrett, once confirmed to the Supreme Court of the United States, will be a Supreme Court justice. No less a Supreme Court justice than Justice Kavanaugh or Justice Gorsuch or Justice Breyer or Justice Kagan or Sotomayor. She will be a justice on full par with them.”

Lee will presumably be a “yes” vote when Barrett’s confirmation comes before the Senate. He has been an outspoken proponent of her nomination and was at the Rose Garden ceremony Saturday when she was introduced by Trump.

Stephanopolous asked about the president’s claims that voting by mail will lead to widespread fraud, noting that FBI Director Chris Wray said last week that there’s no evidence of massive voter fraud in any national election. Lee suggested the president’s fears weren’t unfounded, even while noting that Utah has voted by mail for years.

“It’s worked fine in Utah. Remember, whether we’re talking about mail-in ballots or any other form of potential election fraud, the canard that you can’t prove that it’s happened in the past is very different than saying there’s no reason to worry about it ever,” he said.