In considering Thomas Miles and Cass Sunstein's effort to measure "judicial activism" and the criticism it has generated, I am increasing persuaded that it is impossible to define "judicial activism" in a way that is both 1) useful, and 2) not simply a synonym for incorrect decisions. My tentative sense is that any ideologically or politically neutral definition of "activism" is unlikely to be useful in shedding light on the normative debate over what judicial review should be used for. On the other hand, normatively useful definitions of "activism" will tend to coincide with the analyst's definition of "incorrect decision."

It is certainly possible to define judicial activism in a neutral way. For example, Miles and Sunstein define "activism" in the context of judicial review of regulatory agency decisions as any judicial decision to overrule an agency. Similarly, one can define "activism" in the constitutional law field as any judicial decision to invalidate a statute enacted by a legislature. Such definitions of activism are objective, but not very helpful. Most critics of what they call "judicial activism" don't claim that any judicial decision that invalidates an action by the other branches of government is activist. Instead, they condemn such decisions only if they think they exceed the courts' legitimate authority or misinterpret the relevant law. Thus, knowing that Judge X votes to strike down statutes or overrule agencies more often than Judge Y tells us very little that is useful in determining who is more "activist" in any sense relevant to normative debates about judicial power.

Moreover, both liberal and conservative critics of "activism" often denounce as activist not only decisions that strike down laws, but also those that fail to do so. For a recent liberal example, see here; a recent conservative example is the denunciation of Kelo by some on the right as "judicial activism" (I personally agree that Kelo was wrongly decided, but not because it was "activist").

Of course, we could instead define "judicial activism" not as overruling other branches of government but as doing so without adequate justification. For example, originalists might argue that judges are "activist" when they strike down laws that are not forbidden by the original meaning of the Constitution. In that case, however, the real intellectual work is being done not by the concept of "activism" but by whatever interpretive theory is used to determine whether a given law violates the Constitution or not. For the originalist, the key analytical concept is original meaning or intent; "activism" becomes just another label to attach to decisions that aren't justified on originalist grounds. I don't object if people want to use the word "activist" in this way. But I also don't see how it adds anything to the argument.

There is one group of critics who can use the concept of "judicial activism" in a coherent and analytically useful way. A few scholars - including Robert Dahl and Mark Tushnet on the left, and Lino Graglia on the right - want to abolish judicial review altogether, regardless of the interpretive methodology the judges use. For writers in this camp, it indeed makes sense to define all judicial overruling of the political branches' actions as "activist" and to denounce any such decisions. For the rest of us, however, debates over "activism" are likely to add little of value to the deeper underlying debate over when courts are justified in using their power to strike down the actions of other branches of government.