“Supreme Court Justice Patrick Crooks retiring, taking swing vote with him.” So announced the headline of a post on Madison.com today, reporting on Justice Crooks’s statement that he would not seek re-election. The headline’s wording doubtless occasioned little surprise, as Justice Crooks, more than any other member of the court, has long been accompanied by such labels as “swing vote,” “centrist,” and “moderate conservative”—suggesting that his voting record places him between a liberal minority (Justices Abrahamson and Bradley) and a conservative majority of Justices Prosser, Roggensack, Ziegler, and Gableman.
There is indeed evidence to support labeling Justice Crooks—rather than Justice Prosser, say—as the court’s “moderate,” “centrist,” or “swing vote.” He, and not Justice Prosser, has sided with Justices Abrahamson and Bradley in some politically-charged cases—notably his dissent in Milwaukee Branch of NAACP v. Walker (in which he argued that Wisconsin’s voter ID law is unconstitutional) and his dissent in the recent John Doe case.
In addition to his opinions in these rare high-profile cases, Justice Crooks’s overall voting record finds him joining the liberals somewhat more frequently than does Justice Prosser. Table 1 (covering the seven terms in which the current seven justices have served together) indicates how often both Justice Abrahamson and Justice Bradley voted with Justice Crooks, and how often these two liberals voted with Justice Prosser. Computing the totals for all seven terms, we find Justice Crooks on the same side as the two liberals in 62% of the votes in which all three participated (243/390), surpassing the figure of 53% for Justice Prosser (195/366).
However, one can also make a case that it is misleading to distinguish so sharply between Justice Crooks as the court’s apparent “moderate” or “swing vote” and Justice Prosser as a member of the court’s conservative bloc. To be sure, there is a conservative bloc (as indicated in Table 2, which shows that Justices Roggensack, Ziegler, and Gableman have voted together in fully 90 percent of the court’s cases over the past seven terms. Moreover, after adding up the figures for the seven terms, one finds that Justice Prosser voted with this conservative trio 80% of the time (285/357). The problem for someone trying to distinguish Justice Crooks from Justice Prosser on this score is that Justice Crooks voted with the same trio every bit as often—82% of the time (310/380). Thus, for all types of cases taken together, Justice Crooks joined the court’s three most conservative members just as frequently as did Justice Prosser.
As noted above regarding the general set of all cases, Justice Crooks has sided more often with the liberals than has Justice Prosser. And, as detailed in previous SCOWstats posts, he has joined the liberals more often than has Justice Prosser in certain subsets of cases (involving insurance companies, for example). But SCOWstats has also examined other categories of cases (most recently, Fourth Amendment arguments) in which Justice Prosser voted with the liberals more often than did Justice Crooks.
Further complicating the discussion is the label “swing vote”—frequently applied to Justice Crooks and rarely to Justice Prosser. The term might suit Justice Crooks if one understands the phrase to mean simply that he spreads his votes somewhat more broadly and frequently along the ideological spectrum than does Justice Prosser. I suspect, though, that for most people the term “swing vote” suggests a justice who casts a vote that tips the balance one way or the other in close decisions. And by this measure, Justice Crooks seems less obviously the best candidate for the label.
Consider Table 3. It shows how often over the past seven terms each of the two justices voted in the majority in 4-3 decisions when the other justice did not. Note that Justice Prosser appeared in this role 24 times, surpassing Justice Crooks’s total of 19, indicating that Justice Prosser’s vote was more often crucial in 4-3 decisions than was Justice Crooks’s.
If participation in 4-3 majorities is a reasonable way to determine whether the term “swing vote” better suits Justice Crooks or Justice Prosser, perhaps the most that can be said in favor of Justice Crooks meriting the “title” is that his majority votes were more evenly divided between the liberal and conservative blocs, as shown in Tables 4a and 4b.
Thus, with some exertion and selective emphasis, a case can be made for Justice Crooks as a “swing vote” of sorts, but the distinction often drawn between Justice Crooks and Justice Prosser on this point seems less persuasive than the familiar label suggests.
 To be clear, the figures in the table indicate only how often all three justices in the trio voted together. They were usually joined by other justices as well. Occasionally, one justice in the trio did not participate in a case. In these infrequent instances, if the remaining two justices voted the same way, that case is not included in the calculations. If the remaining two justices disagreed, the case is counted as one in which the trio did not side with each other. Per curiam cases are included.
 The figures in Table 2 were calculated according to rules similar to those outlined in the reference note for Table 1.
 For references to Justice Crooks as a “swing vote,” see (in addition to the Madison.com article cited above) the Milwaukee Journal Sentinel, Justice Crooks’s own Wikipedia article, Wisconsin Public Radio, and FOX11 News.
 Justice Prosser’s total of 23 majority votes without Justice Crooks (adding the totals in Tables 4a and 4b) is one short of his total in Table 3 because in one case (Bethke, 2012-13) the majority consisted of Justices Bradley, Prosser, Roggensack, and Ziegler—that is, only one of the liberals and only two of the conservatives. Thus Bethke does not figure in Tables 4a or 4b.