Yesterday, we compared the Illinois and California Supreme Court’s death penalty caseloads between 1992, the beginning of our California data, through 2010, when Illinois abolished the death penalty.  We found that in the years prior to Governor George Ryan’s 2010 moratorium on executions, Illinois both averaged more death penalty cases per year and was more likely to reverse death judgments in whole or in part.

But of course, there’s a bias in these numbers.  Depending on the time period you’re looking at, California is 2 ½ to three times the size of Illinois in population. All other things being equal, one might hypothesize that death penalty judgments are proportional to a state’s population.  So how do the numbers look if we scale the data for Illinois to put the two states on an equal plane?  To find out, we scaled the Illinois Supreme Court data to account for the population difference, using 1990 census data for the years 1992-1995, 2000 census data for 1996-2005, and 2010 census data for the years 2006-2010.  For example, since California’s population was 2.6035 times what Illinois’ was in 1990, we multiply the Illinois real-world totals by that to arrive at a scaled number (explaining the “fractions of a case” numbers below).

We report the data for total death penalty appeals in Table 748 below.  We see that Illinois’ lead on California increases substantially when we account for the population difference.  In 1992, California handed down thirty-three decisions.  Adjusted for population, Illinois had 59.9.  In 1993, California issued fifteen decisions.  Illinois’ scaled total was 33.85.  In 1994, California handed down seven death penalty decisions, while Illinois had a scaled total of 44.26.  Illinois maintained its wide lead every year until 2002: 46.86 to 15 in 1995; 54.55 to 8 in 1996; 38.18 to 14 in 1997; 51.82 to 13 in 1998; 16.36 to 6 in 1999; 46.36 to 9 in 2000; and 19.09 to 11 in 2001.

Beginning in 2002, everything changed.  That year, Illinois’ scaled total was 13.64 death penalty appeals to 13 for California.  In 2003, California had 20 cases, while Illinois had only 8.18.  In 2004, California decided 21 death penalty appeals, while scaled for population, Illinois had 5.45.  In 2005, California decided 26 cases, while Illinois once again had only 5.45.  In 2006, California had nineteen death penalty decisions, while Illinois’ scaled total was 5.81.  In 2007, California decided twenty-three cases, while Illinois’ scaled total was once again 5.81.  In 2008, California had twenty-five death penalty cases, and Illinois’ scaled total was 2.9.  In 2009, California had 24 cases; Illinois’ scaled total was 8.71.  Finally, in 2010, California decided 24 cases, and Illinois’ scaled total was 11.61.

In Table 749, we report the data for reversals.  Even the unscaled numbers show the Illinois Supreme Court was significantly more likely to reverse death judgments than the California Supreme Court was, and the margin increases when we adjust for population.  From 1992 to 1996, during which time California didn’t reverse outright in a single death penalty case, Illinois’ scaled numbers were 7.81, 2.6, 7.81, 10.41 and 8.18.  In 1997, California reversed one judgment, Illinois none.  In 1998, California again reversed one judgment, but Illinois’ scaled total was 8.18.  California reversed one judgment in 1998 and one in 2003 and 2008.  Illinois’ scaled totals ranged from a high of 8.18 reversals in 1998 and 2000 to a low zero in 2003 and 2006-2008.  California reversed two judgments in 2009, but Illinois’ scaled total was 2.9.

In Table 750, we compare the California Supreme Court’s partial reversals with the death penalty overturned to the Illinois Supreme Court’s scaled numbers.  From 1992 to 1994, California had zero “ARL” death penalty decisions.  Illinois’ scaled total was 10.41 in 1992, 5.21 in 1993 and 7.81 in 1994.  California had one partial reversal in 1995, 1997, 2001 and 2002.  The Illinois Supreme Court’s scaled totals were much higher: from a high of 16.36 in 1997 to a low of zero in 1999.  After the Illinois moratorium, the numbers flipped – California had three partial reversals with penalty overturned in 2003, two in 2004 and 2006 and one per year in 2007 and 2008.  Illinois’ scaled total was 2.9 in 2009 – the only year in which there were any such decisions.

The numbers are similar if we compare California’s total of partial reversals with death sentence affirmed to Illinois’ scaled totals.  Prior to the Illinois moratorium, California had nine in 1992, one in 1993 and 1995, two in 1996 and 1997, one in 1998 and 2000.  Illinois had none in 1995, 1997 and 2000, but in every other year, its scaled totals were much higher – 7.81 in 1992, 2.6 in 1993 and 1994, 10.91 in 1996, 8.18 in 1999 and 2.73 in 2000.

Join us back here next week as we turn our attention to new issues.

Image courtesy of Flickr by Thomas & Dianne Jones (no changes).