Last time, we looked at the lag time from the end of party briefing to oral argument – our proxy for the period in which the Court tentatively decides the case – to see whether there was a correlation to the end result in the case. In other words, do affirmances or reversals consistently take longer to reach argument?

In the next two posts, we’re looking at a different question: is lag time impacted by disagreement on the Court? Today, we’re comparing the average lag time from the end of party briefing to oral argument for civil cases that were decided unanimously to lag time for non-unanimous decisions.

Between 1990 and 1999, non-unanimous decisions averaged a longer lag time in seven of ten years. But perhaps surprisingly, in many years, the effect is not especially high. In 1990, non-unanimous decisions averaged only seven days longer from briefing to argument than unanimous decisions did. In 1993 and 1994, the difference was twelve and eleven days, respectively. On the other hand, in 1997 and 1999, non-unanimous decisions took more than three months longer to reach argument – 104 days in 1997, 105 in 1999. Unanimous decisions took longer to reach oral argument in three years: 1995 (37 days), 1996 (22 days) and 1998 (44 days).

In the next decade, the split was the same – non-unanimous decisions averaged a longer lag time in seven years, unanimous decisions in three. But the differences were getting greater. In only two years was the difference between the two less than a month: non-unanimous decisions averaged 20 days longer in 2002, and non-unanimous decisions averaged 28 days longer in 2006. In four years, non-unanimous decisions took between one and two months longer to reach oral argument: 2000 (35 days), 2003 (47 days) and 2004 (54 days). In 2001, non-unanimous decisions averaged 61 days longer, and in 2007, the difference was 109 days. But in 2005, unanimous decisions took 88 days longer to reach oral argument. In 2008, the difference was 148 days. In 2009, it was still over three months: unanimous decisions reached oral argument in 94 days longer than non-unanimous ones.

In the past ten years, there’s been no clear relationship between disagreement on the Court and lag time from the end of party briefing to oral argument: in five years, non-unanimous decisions took longer, and in five years, unanimous ones did. The degree of difference is all over the map too. In 2010, non-unanimous cases took 30 days longer. In 2012, it was 36 days. In 2015, the difference was 31 days. In 2014, non-unanimous decisions took 214 days longer to reach oral argument than unanimous decisions did. But in 2017, for example, the difference was only 2 days. In 2011, unanimous decisions averaged 77 days’ longer lag time. In 2013, unanimous decisions took 195 days longer. In 2016, unanimous decisions took 84 days longer. In 2018, unanimous decisions averaged only 7 days longer, and so far in 2019, the difference is 38 days (with unanimous decisions taking longer).

What’s the bottom line – does a longer lag time suggest disagreement on the Court? In 19 of the past 30 years, non-unanimous civil decisions have averaged a longer lag time from end of party briefing to oral argument than unanimous decisions.

This suggests a follow-up question: is lag time correlated with the degree of disagreement on the Court? In other words – do 4-3 decisions take the longest, followed by 5-2 and 6-1? Or perhaps more lopsided decisions take longer because the Court is trying to reach unanimity? We take up those questions next.

Image courtesy of Flickr by Greg Balzer (no changes).