Supreme Court Justice Sonia Sotomayor. (Photo: Diego M. Radzinschi/ ALM)

During this month's historic telephonic arguments in the U.S. Supreme Court, Chief Justice John Roberts Jr. interrupted or cut off questioning by his colleagues 11 times, nine of which were of women and all of which were of the court's liberal justices, according to a new study.

Roberts interrupted Justice Sonia Sotomayor the most, even though she had only one of the longest 14 questioning periods, the 10th longest, said the study's author, Leah Litman of the University of Michigan Law School.

Sotomayor tied with Justice Neil Gorsuch in speaking the most per questioning period, but the chief justice never interrupted Gorsuch, even though he had, with Sotomayor, the longest average questioning period.

Roberts, as timekeeper, kept a tight script, limiting lawyers and the justices to a set amount of time. Roberts regularly cut off lawyers, and at times he would tell them "briefly counsel" or to take a minute to "wrap up."

"I doubt CJ Roberts purposely exercises ideological favoritism here. I hope making him aware of the pattern will help him better execute the tough job of running a meeting while participating in it," Richard Primus of the University of Michigan Law School said on Twitter.

Justice Ruth Bader Ginsburg was interrupted many times, even though she had the third shortest average questioning period and the second shortest total time speaking over the two-week session. Like Gorsuch, Justice Brett Kavanaugh was never interrupted, even though he had the longest total talking times in two of the cases where Roberts interrupted other justices—Trump v. Mazars and Trump v. Vance. Those two questioning periods were also two of the three longest questioning periods in any case.

Litman's findings partly reflect a broader 2017 study of oral arguments by Tonja Jacobi of Northwestern University School of Law and Goodwin Procter's Dylan Schweers. In the 2017 analysis, the authors reported that female justices were more likely to be interrupted than male justices and less likely to be allowed to speak when interrupted and that conservative justices also were more likely to interrupt than liberal justices.

Litman acknowledged in the study that the May argument data provide "some very limited insight" into the court's dynamics.

"This snapshot can only tell us so much," she wrote. "There were a mere 10 arguments over a two-week period, and this format was new to everyone. But it is still interesting to see how the court and the various justices adapted to this new format." She added, "The chief justice appeared to try to moderate arguments evenhandedly, and he accomplished that in many respects."

Here are some other findings of the study:

>> The longest questioning periods were during the cases involving the Affordable Care Act's contraception coverage requirement, subpoenas for President Donald Trump's financial records, and the ministerial exemption from anti-discrimination statutes.

>> Roberts spoke less than any other justice. Justice Samuel Alito Jr. spoke the most, followed by Kavanaugh and then Sotomayor.

>> Alito had the single longest questioning period—by more than a minute—in the contraception case, Little Sisters of the Poor v. Pennsylvania. Kavanaugh had the second longest during Trump v. Mazars, the challenge to House committee subpoenas for Trump's financial documents.

>> Ideological balance in questioning time appeared to break down during the Trump cases, Mazars and Trump v. Vance. In the Mazars subpoena case in particular, Alito and Kavanaugh spoke for more time than their colleagues. In the Vance grand jury subpoena case, three of the four justices speaking the longest were conservative justices. "The disparities between the length of time they spoke and the length of time their liberal colleagues spoke is striking," Litman wrote.

For another examination of the first-ever May arguments, empirical scholar Adam Feldman looks at four arguments on his empirical SCOTUS blog. He reported that the argument structure in which Roberts timed questions and responses and called on justices by seniority "allows attorneys more room to participate as they are only asked questions by one justice at a time. The justices appear more engaged by these numbers as well as they both speak more in total and per turn talking."

Read more:

That's a Wrap: What Leading Appellate Lawyers Say About Historic SCOTUS Arguments

'Briefly, Counsel': How Chief Justice Roberts Keeps Phone Arguments Moving

A Few Pauses, and 'Sorry, Chief,' But Supreme Court Pulls Off Historic First

Mobile or Landline? SCOTUS Advocates Prep for First-Ever Phone Arguments