Chief Justice Burger wrought better than he knew by resigning, effective next month, to concentrate on the bicentennial of the United States Constitution.

His departure, and the nomination of two able conservative jurists to fill the vacancy, should afford us a stimulating discussion of the role of the Supreme Court, of justices, and of the Senate confirmation process -- altogether, a splendid curtain-raiser for the Constitution's 200th birthday.

There is a polite myth that when Supreme Court nominees are capable and honorable, the Senate has no decent choice but to reach for the rubber stamp.

But that depends on the nature of the challenge, and in this instance it is considerable. No administration, not even Richard Nixon's, has proclaimed a more aggressively political standard for the selection of judges than Ronald Reagan's. That standard invites a political response.

The nomination of Associate Justice William Rehnquist as chief justice, moreover, involves a special challenge. When an incumbent justice is proposed for the court's center chair -- as Abe Fortas was by Lyndon Johnson 20 years ago, and Harlan F. Stone by FDR in 1941 -- the court's critics of the day have a golden opportunity to review their grievances; and it is seldom resisted.

William Rehnquist's record is that of a brilliant and adroit conservative activist. Although Rehnquist clerked in the 1950s for Justice Robert H. Jackson, a distinguished apostle of "judicial restraint," the Jacksonian legacy has allowed Rehnquist to discover in the Constitution a convenient friendliness to the conservative political agenda he believes in. It should be added that Rehnquist is an exceptionally warm, friendly and considerate man, popular with colleagues of all persuasions.

Antonin Scalia, Rehnquist's anointed successor, is one of a number of bright and scholarly conservatives named to the appellate bench by Ronald Reagan. He has already defined a provocative philosophy of judging, with the law-as-economics flavor of the so-called Chicago school. And like Rehnquist, he seems to find the Constitution congenial to Reaganite social conservatism -- notably, curbs on abortion and on the aggressiveness of the press.

With nominees of this caliber -- and President Reagan is to be congratulated for taking the court seriously -- the decks are cleared for a clean and searching debate, free of animosity and pretense.

That debate is essential because of the policy-making role of the court and the distinct possibility that the federal judiciary may be dominated for a long time by a single outlook.

That policy-making function is threaded through American history, from slavery to Watergate, and it has sometimes provoked political crises on its own, as in New Deal days. Yet it is considered good form, in confirmation proceedings, to dance around issues of policy and to pretend that there's a self-evident difference between "interpretive" and "lawmaking" judges.

Rehnquist and Scalia, sophisticated and scholarly men, know the distinction is simplistic. It's true enough that Supreme Court justices who are good at their jobs commit policy making less noisily than elected officials. But robes aren't veils. Ask those who want prayer back in the public schools or unborn fetuses redefined as "persons" with constitutional rights. The Senate would be remiss in failing to note and examine the administration's designs for the judicial future.

Mix all these ingredients -- nominees of intellect, character, vitality and well-defined views together with the certainty of an ongoing policy-making role for the court -- and you have the prospect of a stirring set of confirmation hearings.

The ordained ringmaster of these proceedings, Senate Judiciary Committee Chairman Strom Thurmond, may well deplore even the cleanest confirmation hardball as improper. If he does, the senator should be reminded of his own hard-hitting interrogation of judicial nominees he happened to disapprove, especially Fortas and Justice Thurgood Marshall.

A well-conducted, serious and searching confirmation process is to be welcomed, not lamented. It presents an opportunity to debate constitutional fundamentals and, incidentally, to test whether recent sloganeering about the original intentions of the Framers is hot stuff or hot air. It should be a a splendid overture to Warren E. Burger's bicentennial observance. And if it isn't altogether melodious, please remember that this is, after all, a democracy.