Here’s a snippet:
The traditional Catholic view—and Alito, Scalia, Roberts, and Thomas in various ways are pretty traditional or orthodox Catholics—is that a person’s political opinions are not governed by revelation as much as by natural law. Natural law is the truth about the rational and social nature of human beings that we can know without revelation’s help. Evangelicals tend to believe that if it were not for the absolute truth of Biblical revelation, something like the libertarian understanding of the absolutely autonomous individual (the being described by Barnett and by the Court in Planned Parenthood v. Casey and Lawrence v. Texas) would describe our lives. The Catholic view is that a consistent individualism is not an adequate account of who we are as natural beings, and so the limits to liberty understood as autonomy can be realized whether or not one believes in the Biblical God. We don’t need to be Christians—either Catholic or evangelical—to see that abortion is wrong.
Catholics are much better than evangelicals in connecting their faith-based perceptions to general-audience arguments on the purpose and limits of Constitutional law. That’s not to say that Catholic justices would use “natural law” to declare statutes and policies un-Constitutional without showing clearly how that law is actually embodied in the text of the Constitution itself. The point is more that those who see natural law as true are more likely to see efforts to understand the judicial power in a radically individualistic and activist way as at war with the way human beings really are.
I think he’s right about "run-of-the-mill" evangelicalism, which is sort of happily voluntaristic, but not about its neo-Calvinist strain, which talks a lot about
"common grace." As with everything Peter writes, it’s pithy and illuminating. 
I wonder whether Calvinism (any strain thereof) might be though of the antithesis of radical autonomy, in that any sort of natural law it recognizes is ultimately swallowed up in it’s absolutist view of predestination and human free will. The Catholic view (Natural Law) is not a synthesis of these two views but rather the truth found in both...
Dear Peter, interesting, as always. Kennedy, however, doesn’t fit the paradigm. True, he was blindsided on the partial-birth abortion decision. But as you well know, he’s a, if not the, leading proponent of "autonomy" jurisprudence on the Court, which is the antithesis of natural law jurisprudence. He was one of the miniscule-three who signed on to the Casey "sweet mystery of life" abomination and all by himself he penned Lawrence, extolling "autonomy" in its spatial and more transcendent dimensions. The autonomous individual, declared Justice Kennedy, is self-defining and the kanon kai metron of the "meaning" of his intimate relations and acts (and no doubt, much more); a sovereign democratic legislature must, as a rule, defer to his definition of the meaning and value or worth of actions and relations undertaken in the name of "autonomy."
Apropos to Kennedy James Davison Hunter’s distinction between Progressive members of a denomination versus Orthodox members may (I repeat: may) be applicable; or Kennedy simply may have imbibed contemporary legal theory with its focus on "moral autonomy"; he certainly is a living constitutionalist (and in invoking it, I don’t see him citing Jacques Maritain’s notion of an evolving natural law.) Bottom line: Kennedy’s a Catholic (faithful or not, I have no idea, nor no interest in determining), but his jurisprudence is contemporary progressive of a most worrisome sort.
Paul,
All that is true enough. But he’s still to the right of the other four,
simply because he can distinguish btwn "abortion rights" and "gay rights" in some measure. So he will be a bit of an ally on the rollback of Roe. But the best argument against Kennedy is that his "liberty" or substantive due process argument in LAWRENCE, consistent libertarian Randy Barnett thinks, will in time be viewed as the beginning of a promiscuous activism that will combine the "economic rights" that the "right" wants to restore and the innovative "personal" (abortion, gay rights etc.) rights favored by the "left." So basically Kennedy, I must acknowledge, is worse than O’Connor (see her more modest concurring opinion in LAWRENCE), but O’Connor will soon be gone.