How Can You Tell if A Justice Is "Liberal" or "Conservative"?:
In the comment thread in my post on today's new Supreme Court decision, an interesting discussion emerged on how you can tell if a Justice is "left of center" or "right of center," "liberal" or "conservative." Are these labels useful or misleading? What's the frame of reference — the Court, the American electorate, or something else? And how can you read views about the law as views about left-right politics?

  These are interesting questions, I think, so let me offer some thoughts. In my view, these labels are a moderately useful shorthand when focused on Supreme Court Justices. The United States Supreme Court picks the cases it wants to hear; every year it picks around 80 cases and issues opinions in that set of 80 cases. As a result, we can look at the political valence of a particular Justice's votes and written opinions in those 80 cases and compare them to the status quo before the Court granted cert.

  My sense is that we tend to apply terms like "liberal" and "conservative" to individual Justices by looking at those cases and asking if Justice X's votes consistently try to pull the law to the left or the right compared to a world in which the Court took no cases. If a Justice consistently votes to pull the law to the right, we label that Justice a conservative; if a Justice consistently votes to pull the law to the left, we label that Justice a liberal; and if a Justice's votes reveal no consistent patterns, we label that Justice a moderate.

  What this means, I think, is that calling someone a "conservative Justice" does not mean that the Justice is conservative politically or votes for Republicans. Conversely, calling a Justice a "liberal" does not mean that the Justice is liberal politically or votes for Democrats. In the case of Supreme Court Justices, the label is just a shorthand signaling that the Justice's votes tend to have the effect of pushing the law in a direction that favors the policy preferences on one side or the other. Thus, we might find a Justice shifting from being a liberal to a conservative even if the Justice's views don't change. A good example is Justice Frankfurter, who was considered a liberal in the 1930s but a conservative in the 1950s in part because the political valence of judicial restraint had shifted.

  Finally, I think these labels are somewhat relative to the Court itself. For example, consider a Justice who never departs from precedent under any circumstances, and always tries to match new cases as faithfully as possible to the old. If a majority of the Court consistently wants to depart from precedent in a way with a particular political valence, the stare-decisis Justice will be labeled in part in opposition to how the other Justices are labeled. If the Justices who want to depart from precedent tend to embrace views consistent with political movement X, then the stare decisis Justice will be labeled not-X. This in part explains Frankfurter's "shift"; he didn't consistently follow the Justices who wanted to shift the law in a way that had a liberal political valence, so he was labeled a conservative at the end of his years on the Court.