What do they know that we don't know? That is what liberals are asking about the nomination of Douglas Ginsburg for the Supreme Court. Ginsburg is a "conservative," but his brief career and skimpy writings establish nothing more than a commitment to free-market economics. Nothing is publicly known about his views on privacy, civil rights, criminal law. More important, nothing is known of his views on the role of the Constitution in sorting out these issues.

Liberals are searching for skeletons in Ginsburg's closet, but this isn't a game. If the administration has actually nominated somebody unobjectionable, there's no need to object. There is much talk of an "ultimate irony" in the works, an Earl Warren-type surprise. Nevertheless, it's hard to believe that the administration, stinging from its Bork defeat, would fall for a closet liberal.

The central anomaly of the failed campaign for Robert Bork was the attempt to present Bork as a man who wouldn't do precisely what Ronald Reagan has spent his political career demanding be done on the Supreme Court. In the end, Bork was defeated for the same reason he was nominated: his views on the great constitutional issues of our day. Ginsburg may make a more convincing moderate, but the question remains: why would Reagan nominate a moderate?

White House domestic policy adviser Gary Bauer calls Ginsburg's nomination "a great day . . . for the country." Bauer couldn't care less about antitrust policy. On the other hand, he's an unapologetic believer in a governmental enforcement of conservative social values. Why isn't he alarmed by Ginsburg's widely touted libertarian streak?

Newsweek quotes another Reaganite saying he'll bet his house that Ginsburg won't vote to overturn Roe v. Wade, the abortion decision. And yet the National Right to Life Committee has endorsed Ginsburg, having been assured by the White House that Ginsburg is "solid across the board." On what basis? Who's kidding whom here?

Ginsburg's lack of a "paper trail" makes the post-Bork rules of the game even more important. The first new rule is that a nominee cannot decline to answer questions, or fudge his answers, about major constitutional questions. No case can be made that Ginsburg is a brilliant constitutional scholar, apart from his specific views. Unlike Bork, he has never written word one about the Constitution. In exercising its advice and consent, the Senate has no obligation to buy a pig in a poke.

Generalities should not suffice. The nominee will express his devotion to civil rights and privacy, and even mean it. That doesn't tell us what he gleans from the Constitution about affirmative action and censorship. It's not fair to accuse liberals of "politicizing" the court by demanding specifics on these issues. Conservatives are just as pas-sionately specific about them. Unless conservatives really do know something about Ginsburg that liberals don't, they shouldbe just as eager to hear his views under oath.

For example, did he or did he not -- as his first wife recalled in a New York Times interview -- recommend a "D & C" (i.e., abortion) for a friend who had been raped? Everything we know about Ginsburg's postmodern life style makes this plausible. It's both pathetic and hilarious that the Justice Department was immediately forced to deny the story. I for one wouldn't want a Supreme Court justice who would recommend otherwise. But I'm happy enough to see the administration's nominee skewered on its own extremism.

An area of questioning that is more urgent in Ginsburg's case than in Bork's is so-called economic liberties. Ginsburg opposes much government regulation. Does he believe -- as a Supreme Court majority did until 50 years ago and as many conservatives, led by Ginsburg's former teachers at the University of Chicago Law School, believe today -- that the Constitution actually forbids many forms of economic regulation? That is, is he not a judicial restrainer but a conservative judicial activist?

The second new rule is that there's no rush. Central to White House strategy is the attempt to make it seem like cheating if Senate Democrats and liberal groups take the time to learn about this unknown quantity who will be making law for two generations. Accusations that "delay" is part of "a political campaign" come oddly from an administration that claims to be carrying the banner of democracy and majority rule into the judicial battlefield.

The third rule is for liberals: don't be jerks. Making a big deal about some penny-ante alleged conflict of interest involving the nominee's investments in a Canadian cable TV company justifiably gives the impression that this is opposition for its own sake.

On the other hand, don't be suckers, either. Harvard law professor Alan Dershowitz, best known as a criminal rights zealot, promises we'll be surprised by the socially liberal views of this "brilliant academic." Where's the evidence? Let's see how Ginsburg does under cross examination.