Any day now, the nine justices on the US Supreme Court are going to hand down the court’s second major decision on Obamacare. The issue in King v. Burwell is a four-word phrase in the Affordable Care Act — “established by the state.”

The “King” in King v. Burwell is a group of Virginia residents who are represented by attorney Michael Carvin. Carvin argues the four words “established by the state”  forbid the federal government from subsidizing health care for residents of states that didn’t set up their own health care exchange. The residents are using an exchange that is not “established by the state.” The government, represented by Solicitor General Donald Verrilli, argues that the intent of Obamacare was to give everyone access to a health care exchange, and to make that access affordable.

The stakes are high. If the court rules against the government and in favor of King and the Virginia residents, six and a half million people will lose their health care subsidies. It would gut Obamacare.

Oral arguments before the Supreme Court in King v. Burwell lasted nearly an hour and a half. The justices asked 113 questions. Timothy Johnson, a professor of law and political science at the University of Minnesota, has studied the oral arguments. “What is probably atypical in this case is that there is a very clear fight, and you saw it publicly, for the votes of the Chief Justice and of Justice Kennedy,” says Johnson.

We asked him to take us through oral arguments in King v. Burwell and point out a few key moments.

You can find the complete audio of the oral arguments here. You can find further analysis at SCOTUSblog.

This segment originally appeared in Episode 59: The Trauma Room.