For several weeks, we’ve been evaluating what we can infer from the pattern of the Illinois Supreme Court’s questions in civil and criminal cases. This week, we turn to a new question: does an active bench mean you’ll be waiting a longer time for the opinion? One can easily imagine that the answer might be yes. If heavy questioning from the Court suggests that the Justices are having difficulty with some point in the argument, a great many questions might mean a particularly long wait for the opinion.

We’ve already measured the average number of questions directed each year to both sides of the argument, and the average time under submission. But absolute numbers aren’t the tools of predictive analytics: correlations are. So is there a correlation between total questions in civil cases and the number of days from argument to decision? Recall that if two numbers move in the same direction perfectly together – 2, 4, 8 and 4, 8, 16, for example – the correlation is positive one. If the variables move in perfect sync, but in opposite directions – more of this equals a proportionally less amount of that – then the correlation is negative one. So does the correlation between total questions in civil oral arguments from 2008 to 2016 and the total days from argument to decision suggest that more questions means a longer wait?

We report the data in Table 429 below. We notice two things immediately about our data: first, correlations are comparatively small, and second, the sign keeps changing, suggesting no stable relationship between total questions in civil cases and days under submission. We measure eighteen variables in the chart – a correlation for non-unanimous and unanimous decisions for each of nine years – but only three times did the correlation exceed 0.5. For 2008, more questions meant less time under submission, regardless of whether the Court was divided or not. For non-unanimous cases, the correlation was -0.066, and for unanimous cases, the correlation was -0.4. For 2009, the correlation for non-unanimous cases turned positive, but was very small: 0.04. Unanimous cases had a correlation of -0.28. For 2010, the correlations were still opposite to the sign our theory leads us to expect: for non-unanimous cases, the correlation is a moderately large -0.58, and for unanimous cases, the correlation is a small (and negative) -0.17. For 2011, both sides of the civil docket had turned in the expected direction – for non-unanimous cases, the correlation was 0.37, and for unanimous cases, the correlation was 0.2. For 2012, the correlation among non-unanimous cases was just a bit bigger, at 0.41, but for unanimous cases, it had turned negative again, at -0.22.

Over the past three years, the relationship between total questions in civil cases and days under submission has been weak, and often the reverse of what we expect. In 2013, non-unanimous cases had a correlation of 0.33, but unanimous decisions had a correlation of -0.23. In 2014, both measures were negative – non-unanimous cases had a strong correlation of -0.78, and unanimous decisions had a correlation of -0.12. For 2015, both correlations were quite small: non-unanimous cases had a correlation between questions and lag time of -0.2. Unanimous decisions had a correlation of only 0.05. Last year, the correlation for non-unanimous cases was relatively strong at 0.71. The correlation between questions and lag time for unanimous decisions was -0.3.