For the past two weeks, we’ve been analyzing the voting dynamics on the Illinois Supreme Court, determining which Justices voted together most and least often over time in non-unanimous cases.  Today, we conclude our analysis with the criminal docket between 2010 and 2015.

Just as we saw on the civil side, Justice Burke’s closest match in criminal cases appears to be Justice Freeman.  She agreed with Justice Freeman in 71.43% of non-unanimous criminal cases in 2010, 100% in 2011, 90% in 2012, 84.62% in 2013, 85.71% in 2014 and 100% last year.  Agreement rates with the two other Democratic Justices were considerably lower.  Justice Burke and Chief Justice Kilbride agreed in 14.29% of non-unanimous criminal cases in 2010, 45.45% in 2011, 30% in 2012, 53.85% in 2013, 42.86% in 2014, and 50% in 2015.  Justice Burke agreed with Justice Theis 50% of the time in 2010, 45.45% in 2011, 60% in 2012, 23.08% in 2013, 28.57% in 2014, and 66.67% in 2015.  Justice Burke’s agreement rates with the Republican Justices were significantly lower.  She voted with Justice Thomas in 14.29% of non-unanimous criminal cases in 2010, 0% in 2011, 50% in 2012, 53.85% in 2013, 42.86% in 2014 and one-third of the time in 2015.  Her agreement rate with Chief Justice Garman was quite similar: 7.14% in 2010, zero in 2011, 50% in 2012, 46.15% in 2013, 42.86% in 2014, and one-third in 2015.  Justice Burke’s agreement rate with Justice Karmeier was virtually identical to the rate with Chief Justice Garman.

Interestingly, the Republican Justices have disagreed somewhat more often in the past three years than they did earlier.  Justice Garman agreed with Justice Thomas 92.86% of the time in 2010, and with Justice Karmeier, 100%.  Her agreement rates were 100% with both Justices in 2011, and 80% with both in 2012.  In 2012, Justice Garman voted with Justice Thomas in 76.92% of cases, and with Justice Karmeier in 69.23%.  In 2014, Chief Justice Garman agreed with Justice Thomas in 100% of non-unanimous criminal cases, but with Justice Karmeier only 71.43% of the time.  For 2015, Chief Justice Garman’s agreement rate was down to two-thirds with both Justices Thomas and Karmeier.  Those rates are comparable to Chief Justice Garman’s agreement rate with Justice Theis in criminal matters: 54.55% in 2011, 70% in 2012, 76.92% in 2013, 57.14% in 2014 and 66.67% in 2015.  Meanwhile, her agreement rate with Justice Freeman is the mirror image of the result with the other Republican Justices – very low initially, but rising significantly in the last few years.  Chief Justice Garman and Justice Freeman agreed in 21.43% of non-unanimous criminal cases in 2010, zero in 2011, but 40% in 2012, 61.54% in 2013 and 57.14% in 2014, before falling back to one-third in 2015.

Justice Freeman’s agreement rate in non-unanimous criminal rates was relatively similar for each of the other Justices.  He agreed with Chief Justice Kilbride in only 28.57% of cases in 2010 and 20% in 2012, but 45.45% in 2011, 69.23% in 2013, 57.14% in 2014 and half in 2015.  Justice Freeman agreed with Justice Theis in 45.45% of non-unanimous criminal cases in 2011, 50% in 2012, 38.46% in 2013, 42.86% in 2014, and two-thirds in 2015.  Justice Freeman’s agreement rates with Justices Thomas and Karmeier are quite similar: in 2010, 28.57% for Justice Thomas and 23.08% for Justice Karmeier; in 2011, zero for both; in 2012, half for Justice Thomas and 60% for Justice Karmeier; in 2013, 69.23% for Justice Thomas and 61.54% for Justice Karmeier; in 2014, 57.14% for both, and in 2015, one-third for both.

At times since 2010, Justice Kilbride has voted quite similarly to Justices Thomas and Karmeier in criminal matters.  For 2010, his agreement rate with Justice Thomas was 85.71%, with Justice Karmeier 92.31%.  In 2011, both rates fell to 54.55%, and the next year, both fell to 40%, but in 2013, Justice Kilbride agreed with Justice Thomas 84.62% of the time, and with Justice Karmeier in 92.31% of cases.  Their agreement rates for 2014 were 71.43% (Justice Thomas) and 100% (Justice Karmeier) before both fell to 50% in 2015.  Meanwhile, Justice Kilbride agreed with Justice Theis in 81.82% of cases in 2011, half in 2012, 69.23% in 2013, 85.71% in 2014 and half in 2015.

In view of these results, it’s no surprise that Justices Thomas and Karmeier have been in relatively close accord on criminal matters since 2010.  Their agreement rate was 92.31% in 2010, 100% in 2011, 90% in 2012, 92.31% in 2013, fell to 71.43% in 2014, but was back to 100% in 2015.  Justices Thomas and Theis are on the same side only about half the time in non-unanimous criminal cases.  Their agreement rate was 54.55% in 2011, 70% in 2012, 53.85% in 2013, 57.14% in 2014 and two-thirds in 2015.  Justice Karmeier’s agreement rate with Justice Theis was quite close to those numbers: 54.55% in 2011, 70% in 2012, 61.54% in 2013, 85.71% in 2014 and two-thirds in 2015.

Join us back here next Tuesday as we turn our attention to a new subject in our ongoing analysis of the decision making of the Illinois Supreme Court.

Image courtesy of Flickr by Conal Gallagher (no changes).