All of official Washington is on edge. Soon the capital city will be treated to one of its most cherished rituals -- the spectacle of a big hearing. The Senate Judiciary Committee has scheduled four full days to consider the nomination of John Roberts to the Supreme Court.

At the risk of heresy, I want to ask a simple question: Why? Why are we having these hearings? After all, there is little doubt that Roberts will be confirmed. Unless he has a secret history that will, miraculously, soon be revealed, the final result -- ready confirmation by a solid majority -- is a foregone conclusion. Even the votes against Roberts -- such as Sen. Barbara Boxer's promise to vote "no" unless Roberts expressly agrees to uphold Roe v. Wade -- are unlikely to change.

It's worth remembering that Senate judicial confirmation hearings are a relatively new invention. In the first 150 years, no court nominee ever testified, and the first -- Attorney General Harlan Fiske Stone -- did so only to respond to allegations of prosecutorial misconduct in the investigation of a senator. Justice William O. Douglas didn't testify in 1939, and in 1949, Sherman Minton refused to appear (even though the Senate asked him to) on the ground that his record as a former senator and sitting appellate judge spoke for itself. Yet both Douglas and Minton were confirmed.

It wasn't until relatively recently -- in 1955 -- that it became routine practice for nominees to appear before the Senate. And it wasn't until Justice O'Connor's hearing in 1981 that the nominations were televised.

So, again, why have hearings? Senate votes aren't affected, and history demonstrates that the Senate is perfectly capable of judging a nominee without them -- if it wants to. Yet, in this case, we will hear not only from the nominee, but also, more importantly, from all of the interest groups, both pro and con, who are vitally interested in the nomination.

And that, I think, explains why we will have the hearings. They aren't for the senators, who likely know how they will vote. The hearings are for the interest groups and their constituents.

When Sen. Boxer says she will vote "no" unless Roberts promises to support Roe, it isn't as if she actually anticipates that he will come to the hearing sporting an "I support Roe" button on his lapel. Likewise, when conservative senators ask about Roe, they won't be expecting Judge Roberts to promise to overrule it.

Rather, their audiences are different ones -- principally, constituents who have voted for them (and whom they hope will vote for them again). More significantly, the hearings are for the interest groups who gather around the Supreme Court as the ultimate arbiter of American culture today. For Sen. Boxer, it is "NARAL Pro-Choice America" that matters most.

To see this, look at one of Washington's favorite maneuvers that occurred in mid-August -- the trial balloon. Anonymous Democratic senators were quoted as saying that they thought they'd give Roberts a pass. But the balloon popped. The adverse response from liberal interest groups was immediate, and the very next day Sen. Patrick Leahy, D-Vt., raced to characterize Roberts as a "radical" from the "far right wing" of the Republican party.

And that's sad. It reflects the ultimate triumph of politics over law and effectively reduces the Supreme Court to an ersatz legislature -- a pale imitation that short-circuits democratic institutions.

Perhaps it would only address a symptom, and not the cause, but shouldn't the Senate consider returning to its historical tradition? Hearings should be about the qualifications of the nominee, not public posturing for special-interest groups. Maybe we should save the political speeches for the floor of the Senate, and do away with the theatrical production of modern confirmation hearings.

Paul Rosenzweig is a senior fellow in the Heritage Foundation Center for Legal and Judicial Studies and a former Justice Department lawyer.