Between 2000 and 2009, appellants’ amici wrote 141 amicus briefs while respondents’ amici wrote 90.  The margin in winning percentage between the two sides was almost exactly the same as on the civil side.  Appellants’ amici won 68.09% of the time, while respondents’ amici won 43.33% of their cases.

Leaving aside the minor players – one appellants’ amici each in property crimes, violent crimes, driving offenses and financial crimes and four in cases involving drug offenses – the leading area of law was habeas corpus, where 92.31% of appellants’ amici wound up on the winning side.  Appellants’ amici in sentencing law cases won 83.33% of the time.  Constitutional law appellants’ amici won 71.43%.  Appellants’ amici won two thirds of the time in juvenile justice issues and attorney discipline cases.  The lowest winning percentage by a significant player was for appellants’ amici in criminal procedure cases, who won only 56.52% of the time.

Respondents’ amici were on the losing side in all their cases in sentencing law, violent crimes, sexual offenses, property crimes and drug offenses cases.  The leading respondents’ amici were in juvenile justice cases with a winning percentage of 76.47%.  Respondents’ amici in criminal procedure won 60.87% of their cases.  Habeas corpus respondents’ amici won only 36.36% of the time – a considerable distance from appellants’ amici, who won 92.31%.

Join us back here later this week as we address the data for the years 2010 through 2020.

Image courtesy of Flickr by Pedro Szekeley (no changes).