Why does the supposedly nonpartisan Supreme Court split so often along ideological lines, with the four conservatives locked in combat against the four liberals and the eclectic Justice Anthony Kennedy determining which faction wins?

And why do all of the justices so often find in the Constitution a mirror image of their own political and policy views on issues as diverse as abortion, race, religion, gay rights, campaign finance, the death penalty and national security?

The justices strenuously deny voting their own policy preferences. So, are they insincere?

Well, no, except that none admits that interpreting the Constitution is an inescapably subjective enterprise in which policy and political preferences unavoidably play a big part. This is especially true at the Supreme Court, which is not strictly bound by its own precedents.

Even a rigorously apolitical justice passionately committed to "applying the law" would often find no clear law to apply.

Conservative (and some liberal) "originalists" are correct in saying that justices who seek to override the text and original meaning by invoking the "living Constitution" have nothing to guide them but their own policy preferences — and precedents, which can be overruled.

But originalists cannot avoid subjective judicial policymaking, either, for at least four reasons.

First, there has never been a consensus on the original meaning of expansive constitutional phrases such as "due process of law" and "equal protection of the laws," or on how to handle the tensions among various other provisions. The Framers themselves often differed on how to apply the Constitution to specific cases.

Second, any consensus that may have once existed about the meaning of the most important provisions has been erased by time and by the revolutionary changes in the way Americans live.