Over the past few weeks, we’ve been looking at the data on the patterns in the Illinois Supreme Court’s questions at oral argument to see what we could conclude about the likely future progress of a case. Yesterday, we looked at whether particularly active questioning from the Court suggested that the case might be under submission from oral argument to opinion for a longer time.
Today, we address a similar question: does active questioning suggest that the Court’s majority opinion will be longer?
We can imagine scenarios at oral argument in which the answer might be yes. For example, a particularly difficult case, or one with a large number of issues, might lead both to heavy questioning from the Court and to a longer-than-average majority opinion.
As we noted yesterday, total questions from the Court is a widely dispersed variable, with a mean value of 31.155 questions, and a spread ranging from a low of 1 to a high of 81 questions. The standard deviation of the total questions variable is 15.136.
Because the Illinois Supreme Court tends to write concise opinions, the data on majority opinions shows considerably less spread. The mean value for pages in the majority opinion is 13.422. Opinions have ranged from one-page per curiams to a high (in civil cases) of only 41 pages. The standard deviation for pages in the majority opinion is 6.259 – less than half the spread in total questions.
The scatter plot seems to show a slight positive relationship between total questions and opinion length:
The correlation between total questions and length of the majority opinion confirms the plot. The correlation is 0.08997. So unlike our findings with time under submission yesterday, the sign of the relationship is positive. Although the two variables are more strongly correlated that either of our previous posts (questions margin and losing margin in votes; and total questions and time under submission), total questions asked at oral argument is at best only a slight indicator that the majority opinion might be longer.