Especially while the Miers nomination was still in play, but still occasionally since then, I've been hearing a mantra from judicial conservatives, and I'm trying to figure out what it means. The line is that a Supreme Court nominee needs to have a comprehensive theory of judicial interpretion. Otherwise, we're going to have someone without any judicial principles who will simply legislate preferred social policies from the bench. See, for instance, Kenny Pearce. I agree with most of what he says, actually, but I'm trying to figure out what counts as a comprehensive theory of judicial interpretation.
Kenny's example is Justice Scalia, whose vote is thoroughly predictable due to having a clear judicial philosophy, while Justice O'Connor has been the opposite. I'm not sure predictability is necessarily a sign of a clear judicial philosophy. Someone might be predictable precisely because they do favor a certain set of outcomes and base their decisions solely on such considerations. Some do accuse Scalia of not being truly consistent with his comprehensive judicial philosophy when he doesn't want to be (which I think is at least a worry with his affirmative action position). But he does have an official one, however consistent with it he may or may not be in practice. So it's not having one that's important. It's following one. And it's not just following any old one, because it would be a comprehensive judicial philosophy to say that we should simply uphold all lower court holdings. What matters is having a good judicial philosophy, not just having any old comprehensive view.
Nonetheless, I'm interested in the question of what it is to have a comprehensive judicial philosophy and why that's even necessary. Does Judge Alito, for instance? He seems not to be an originalist, anyway, at least not in the absolutist way that Justices Thomas and Scalia claim to be. Chief Justice Roberts flatly denies that he's one. Maybe these two are just more honest about other principles that enter into their decision, but the question I have is whether you need to have a comprehensive theory that goes only on some central standard like original meaning or original intent, taking such a principle as absolute. Both would say that they pay attention to a variety of factors. Roberts denies that he has such a comprehensive theory. I'm wondering why this is bad, for one. I'm not even sure it's right to deny it the status of a comprehensive judcial theory, either.