Justice Elena Kagan recently told University of Wisconsin Law School students that arguing before the U.S. Supreme Court is “pretty much a nightmare” for lawyers, but not for members of the Supreme Court Bar.

“We are so, so lucky,” Kagan said during a Sept. 8 conversation with Dean Margaret Raymond, a longtime friend of the justice. “We have an extremely high caliber bar.”

Many of the arguments, she said, are made by “repeat players” who “really know the court, who know the process of arguing before the court, who know what it is we like, who know what they should be doing, what they shouldn't be doing.”

Kagan said that “arguing in front of courts is difficult, but in front of the Supreme Court it's pretty much a nightmare because you have a lot of very, very active people who ask a ton of questions.”

She continued: “It's very rapid fire. You have to have really thought through stuff before you get to the podium. Often the justices aren't really asking you questions; they don't really care about the answers you give. They're making points to their colleagues. I say this not in a pejorative way. I do it all the time, and I think it's actually an important part of the process that we're talking with each other up there. But it makes it extremely hard for the lawyers who want to occasionally interject at some point. It's a good thing to realize so let's give these people a little bit of a break.”

The emergence of a specialized Supreme Court Bar hasn't gone without notice—and criticism.

A Reuters investigation published in 2014, pointing to legal scholars, said the repeated appearance of the same advocates “has turned the Supreme Court into an echo chamber—a place where an elite group of jurists embraces an elite group of lawyers who reinforce narrow views of how the law should be construed.” A 2008 paper from Richard Lazarus, a Harvard Law School professor, confronted and questioned the rise and influence of the “elite private sector group of attorneys” that he called the modern Supreme Court Bar.

Kagan said seeing good lawyering by the high court bar taught her that there is no single right way to make an argument. She recounted an anecdote about returning from a court conference when, because of a flight delay, she spent several hours in the airport with two veteran high court advocates. The two attorneys had dramatically different argument styles. In discussing argument styles, one of the lawyers described himself as a hot lawyer and the other as a cold lawyer, she recalled.

“One gets up to the podium and the place just like throbs with energy,” Kagan said. “Everybody leans forward in their chairs. There's just so much tension and energy in the air. He's just tremendous, knocking everything out of the ballpark. The other is calm, cool and collected as can be. He just sort of cools down the temperature of the room, and is Mr. Reasonable Man. Surely you have to believe everything he says because he says it in such a calm kind of way, sort of a slowwww way.”

Both lawyers, however, she added, are tremendous advocates. “So a lot of it is personality, a lot of it is just what feels comfortable, but that said, you've got to listen to the judges,” Kagan said.

In an earlier recounting of the anecdote, Kagan said the two lawyers with her that day were Sri Srinivasan (Mr. Cool)—now a judge on the U.S. Court of Appeals for the D.C. Circuit—and Kirkland & Ellis partner Paul Clement, the Mr. Hot at the podium.