One of the problems in answering questions as to how liberal or conservative a judge might be is coming up with some acceptable measure of ideology. There is no generally accepted measure of lower court ideology. A judge’s own partisan affiliation and the ideology of a judge’s appointing president have often been employed as useful surrogates of judicial attitudes. Scholars have sometimes ignored the ideology of the judge, and inferred his or her ideology from that of the appointing president. For example, Tate and Handberg (1991) proposed a measure of the ideology of the appointing president: -1 for ideologically conservative and presidents, 0 for nonideological presidents, and 1 for ideologically liberal presidents.
A recent and now widely used ideology measure was devised by Giles, Hettinger and Pepper (2001). This uses the Poole Nominate scores of the home state senators or of the nominating president if there is no home state senator of the same party as the president. The scores can range from -1 (most liberal) to +1 (most conservative). If we examine the nomination of Sotomayor to the United States District Court in 1992, she was nominated by a Republican president with a Republican home state Senator – Al D’Amato. That would peg her ideology at the time at .14, very moderate and just slightly conservative, befitting a then Republican Senator representing a very Democratic state. However, it was well known that both New York Senators employed a courtesy relationship in reference to judicial appointments. Depending upon the party of the president, the Senator of the same party would get 3 out of every 4 judicial appointments and the other Senator 1 out of every 4. Sotomayor was clearly an appointment of Daniel Moynihan. So if we peg the ideology to Moynihan, -.562, then Sotomayor is very liberal. Of course this shows one of the problems with this particular measure, and indeed with any measure of ideology.
Her appointment in 1998 to the Second Circuit presents no such problem. Clinton was president, so we can use Moynihan’s score, which at this time was even more liberal, – .614. Thus by using the Giles, et. al. measure, Sotomayor is very liberal.
Another measure was developed by a former colleague of mine, Dave Nixon, developed a more direct measure for each judge. We first used this in a paper published in the Washington University Journal of Law and Policy (2003), and Scott Graves and I use it in our forthcoming book on recess appointments and I use it some other publications and it will be in another forthcoming book of mine of Courts and Tax policy. The calculation begins by using the nominate scores of congressional representatives who later served as federal judges as a formula for determining a nominate score comparable to Nominate scores. The formula then uses various circumstances surrounding the appointment such as unified government, wartime, party of the judge and party of the president, among other factors. Unlike the Giles, et. al. scores the Nixon/Howard scores allow for differences for judges even if appointed from the same state by the same president. The scores range from about -5, most liberal to + 5, most conservative.
Given all that, what is Sotomayor’s ideology based on both appointments? Although appointed first by a Republican president and then by a Democratic president, her ideology is similar in both, particularly since both took place under divided government. Her first score is – .21, while her second is -.28. Both liberal, to be sure, but both more moderate than the Giles, et. al. score.
Which is correct, what better predicts her future voting? Who knows, perhaps neither. We have not even begun to discuss the Segal Cover measure, more on that later.