[For the benefit of readers who don’t read both our Illinois and California blogs, the first paragraph immediately below is reprinted from our first post of this week on the Illinois Supreme Court Review.]

In the past twenty years, several academic researchers have extended the study of amicus briefs to state courts of last resort.  In 2001, Professors Paul Brace and Kellie Sims Butler published “New Perspectives for the Comparative Study of the Judiciary: The State Supreme Court Project,” 22 The Justice System Journal 3 (2001).  They assembled data for amicus filings in all fifty state courts of last resort for all cases decided between the years 1990 and 2001.  They concluded that in a total of nineteen states (Arkansas, South Dakota, Idaho, North Dakota, Iowa, Nebraska, Texas, Wyoming, Montana, Hawaii, Rhode Island, Arkansas, South Carolina, Maine, Nevada, Indiana, Virginia, West Virginia and North Carolina), less that 5% of their total cases resulted in amicus briefs.  On the other hand, in five states (Oklahoma, Oregon, Michigan, New Jersey and California), 25% or more of all cases resulted in amicus briefs.  California led the way at just over 37%.

We began by replicating the data from the study, tracking the yearly percentage of civil cases with at least one amicus brief.  The number started out quite high and went even higher; in 1991, 77.5% of all civil cases drew at least one amicus brief.  By 1997, that figure had risen to 88%.  After a brief dip, in 2001, 89.58% of all civil cases had at least one amicus.  The figure topped out for this first half of our study period in 2003, when 90.91% of all civil cases had at least one amicus brief.  For the entire period 1990 through 2001 – the same years covered by the study – we found 572 cases with amicus briefs out of 1,195 total cases.  Thus, during these years, 47.87% of all cases at the California Supreme Court had at least one amicus brief.

Next, we track the average number of amicus briefs per appellant in civil cases.  Interestingly, although the percentage of cases with at least one amicus edged up during these years, the average number of briefs per appellant didn’t, suggesting that the increase was not so much in the number of briefs being filed in the same sorts of cases as it was briefs being filed in a wider cross-section of cases.

In 1990, appellants averaged 1.28 amicus briefs per case.  That rose to 1.61 in 1994 and 2.1 in 1997.  After a one-year dip, the average rose back to 2.02 in 1999 and 2.18 in 2000.  The number dipped again, this time for two years, before topping out at 2.7 briefs per case in 2003.

For the most part, respondents averaged fewer amicus briefs per year than appellants.  The average started at 0.97 average briefs in 1990.  By 1995, it had risen to 1.37, and by 2000, to 1.65.  After a slight dip for the three years following, the average reached 1.77 briefs per case in 2004.

Join us back here next time as we review the data for the criminal docket during the same years.

Image courtesy of Flickr by Eric Kilby (no changes).