This post was written by Tom Goldstein, with data collected by Jason Harrow.

As we enter the last argument sitting of the Term, it is worth commenting on the principal topic of conversation in the Bar. In January and December, a significant amount of attention was given to the Court’s pace in granting certiorari, which had slowed and then picked up in time to add an unexpectedly large number of cases for April. Now, the principal topic of discussion is how quickly the Court is deciding cases.

The answer is that decisions have been issued very slowly, though there are important caveats to all the numbers.

Here are the basic figures. Between O.T. 2000 and O.T. 2005, the Court by the eve of the April sitting had issued between 36 and 43 decisions. This Term, the figure is 27, one quarter below the lowest number for any of the previous five terms. The argument calendar for the early part of this Term was largely full, so the drop-off is notable.

Those numbers are somewhat (but not dramatically) inflated by per curiam opinions, however, which were more prevalent in previous Terms and which take less of the Court’s time because those cases are not briefed and argued on the merits. For example, although by this point last Term there were 43 decisions, only 32 were after argument. (The number for the previous Term was 34.) This Term, so far there have been 23 post-argument rulings, still a notable decline.

Another relevant measure of production is the number of pages of decisions. At this point last Term, the Court had issued 672 pages of opinions. This Term, the number is 545.

One possible explanation for the falloff in output that I considered was that the Court is taking longer in its internal deliberations in an effort to produce greater unanimity, which is an expressed goal of the Chief Justice. That may indeed be occurring; until we see the opinions released later in the Term, there is no way to know for sure. But the numbers so far do not suggest a trend towards greater unanimity. At this point last Term, of the post-argument decisions, 17 were unanimous and 3 were 5-4; this Term, 6 are unanimous (far fewer) and 5 are 5-4 (more). Last Term set a perhaps unrealistic standard for unanimity, however, as the Court appeared to avoid controversial rulings in several cases in the transitional period of Justice O’Connor’s departure.

The number of separate opinions is also intriguing. Last Term, there were 53 individual opinions at this point. This Term, with substantially fewer decisions, there nonetheless have still been 50 individual opinions. But last Term, Chief Justice Roberts’ first, is not particularly representative: by this point in Chief Justice Rehnquist’s last Term (O.T. 2004), there had been 89 individual opinions encompassing 905 pages. (Of note, in that Term, the Court impressively managed to decide United States v. Booker in roughly three months, producing 6 opinions spanning 124 pages.) Chief Justice Roberts’ tenure has thus been marked by fewer separate opinions, consistent with his goal of minimizing the fragmentation of the Court’s opinions when possible.

From outside the building, there is no obvious cause for the Court’s slowed decisionmaking. The best guess from my perspective is that there is a natural transition that comes with the change in the Court’s composition, including its leadership. Before the addition of two new colleagues, the Justices (who had sat together for more than a decade) could write with great confidence in where the rest of the Court would come out and what it would find acceptable. Now there is naturally more hesitancy and perhaps there are more and longer exchanges between the chambers. The topic receives attention at all, perhaps, only because of the reduction in both cert. grants and written opinions in a single Term.

It bears stating that the Court’s reduced output has had no adverse consequences. No decision is pending in an urgent matter. And the Supreme Court still issues rulings faster than almost any other court. No one doubts that the Justices will decide this Term’s cases before the summer recess begins in July.