About the authors
Tonja Jacobi is a professor at Northwestern Pritzker School of Law.
Matthew Sag is a professor at Loyola Law School of Chicago.

The U.S. Supreme Court building. (Jonathan Newton/The Washington Post)

Justice Clarence Thomas is seldom discussed without mention of his unusual silence. Appointed in 1991, he has spoken fewer than three words, on average, per case at oral argument. In contrast, Justice Stephen G. Breyer speaks an average of 745 words per case. Thomas went 682 cases without uttering a single word between 2006 and 2016. When he eventually broke that silence, it made national news.

But such silence is unusual only today, at a time when combative justices argue with — and interrupt — one another. Twenty-five years ago, things were quite different. In a new study examining the full transcripts of every oral argument over 55 years, from 1960 to 2015, we found that judicial silence used to be quite ordinary. For most of the Supreme Court’s modern history, it was common for multiple justices in a given case to not speak, and it wasn’t unusual for justices to barely speak for entire terms.

Before 1995, it was common for one or two or more justices to be silent in any given case. But the modern trend is away from reticence at oral argument. On average, 2.54 justices were silent per case in the pre-1995 era. Since 1995, that number has dropped to an average of 1.35, and to a mere 0.41 without Thomas.

Many other forms of judicial behavior also changed in the mid-1990s. Starting in 1995, the time that justices spent speaking during oral argument skyrocketed, leaving the advocates with far less of the 60-minute argument to make their cases. In the past 20 years, each justice has spoken more than 205 additional words, on average, in each case; this translates to more than 1,800 additional words per case for the court as a whole, even when controlling for factors such as case salience and issue area. The justices as a group have taken an additional 13 minutes of argument after 1995 than before, an increase of 22 percent.

What caused these trends? Many court commentators theorize that the pugnacious Justice Antonin Scalia altered oral argument, but his arrival in 1986 was associated with little change. Nor did the contracted judicial conference that Chief Justice William H. Rehnquist introduced make much difference, nor the Senate’s controversial rejection of nominee Robert H. Bork. Rather, behavior at the Supreme Court changed in response to a radical increase in political polarization.

The 1994 Republican Revolution, led by Rep. Newt Gingrich (Ga.), coincided with a rapid rise in polarization. Ideological distance between the two parties grew, and the number of moderates in Congress plummeted. Norms of bipartisan lawmaking began to erode, and eventually the Republican majority impeached a popular Democratic president.

During this period, the justices’ questions to litigants barely increased, but nonquestions — occasions when the justices made statements, rebutted their colleagues and presented arguments — rose precipitously. Since 1995, the justices have made comments almost three times as often as they have asked questions, with an average of 7.7 questions to 20 comments. Together, the justices have made more than 100 additional comments per case since 1995. Rather than inviting advocates to explain their positions, the justices are often making the cases themselves.

The link with polarization is clear: The justices now disproportionately disrupt the side that they ultimately rule against. Before 1995, there was, on average, a 102-word difference per justice in words spoken to friend and foe. Now, the difference has more than doubled. After 1995, the average difference in words spoken to friend and foe was 188 per justice; by 2015, it had risen to 215 words per justice, almost 2,000 words per case, an increase of 115 percent over the average for the pre-1995 period.

In fact, this understates the extent of the justices’ selective confrontation. The justices generally direct their true questions to the side they support and their comments to the side they oppose. The difference, again, increased massively since 1995.

Justices also began more frequently to supply answers through leading questions and to step in with deflection and rebuttal. At oral argument in Dean v. United States last year, after Justice Sonia Sotomayor repeatedly came to the aid of a struggling advocate, he mistook Sotomayor for Justice Elena Kagan. “She’s Justice Sotomayor,” Kagan told him. “She was the one helping you.” It was an unusually frank recognition of what oral arguments have become: a chance for the justices to support their side over the other one.

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