From his first argument on the Supreme Court last year, Justice Neil Gorsuch established himself as an active questioner, flouting the traditional break-in period to the reported consternation of some colleagues.

By the count of at least one prominent appellate lawyer, Walter Dellinger of O'Melveny & Myers, Gorsuch peppered attorneys with 45 questions that day in April 2017. So it was with some surprise how Gorsuch participated in Monday's argument in the latest challenge to fair-share union fees: He did not ask a single question.

Reflecting on the loquacious justice's silence—at least in the case Janus v. American Federation of State, County, and Municipal Employees—Gibson, Dunn & Crutcher partner Ted Olson could only offer speculation Tuesday on a panel discussion in Washington hosted by the National Association of Attorneys General.

Ted Olson of Gibson Dunn.

“The transcript of the argument is very interesting and illuminating to read, and I read it over yesterday afternoon and this morning again. You see that split of the four members—[Stephen] Breyer, [Ruth Bader] Ginsburg, [Elena] Kagan, [Sonia] Sotomayor—on the one side and the other four on the other side. And who didn't say a thing? Justice Gorsuch didn't utter a sound,” said Olson, who served as U.S. solicitor general under the George W. Bush administration.

“He's not bashful,” Olson added. “He knows he's in the middle of this thing. He knows that he's the vote that's going to tip it one way or the other. And he knows how he's going to come out. But he decided to be very coy. The very next argument yesterday morning, he was all over the place.”

Though he has consistently voted with the court's conservative wing, Gorsuch finds himself the potential swing vote in the union-fees case because the justices were deadlocked 4-4 the last time they took up the issue. The justices heard a similar case in 2016, Friedrichs v. California Teachers Association, and appeared ready to rule that mandatory fees to public sector employee unions were unconstitutional. But the death of Justice Antonin Scalia left the court deadlocked.

Legal scholars pondered Gorsuch's reticence in the unions case, sharing thoughts on Twitter, but there were no easy conclusions to draw. “We should know by June,” tweeted Jonathan Adler, a professor at Case Western Reserve University School of Law.

Gorsuch's style on the bench has reportedly grated on his fellow justices. On the “First Mondays” podcast, NPR reporter Nina Totenberg in October said Gorsuch “ticks off some members of the court—and I don't think it's just the liberals.” Justice Clarence Thomas in November pushed back against that idea, saying in a Fox News interview: “He is a good man. I have no idea what they are talking about.”

Monday's silence wasn't the first time Gorsuch was mum on the bench. He didn't ask questions in the employment arbitration case Epic Systems, argued on the first day of the term. And stayed out of the fray in the Ohio voter-roll case in January.

That's not to say Gorsuch has stayed quiet in every high-visibility case. He fired off questions at, among other arguments, Masterpiece Cakeshop and the Wisconsin redistricting case Gill v. Whitford.

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