This afternoon, Sen. John Cornyn, chairman of the Senate Judiciary Committee’s subcommittee on the Constitution, will convene a hearing on the following subject: “Judicial Nominations, Filibusters, and the Constitution: When a Majority is Denied Its Right to Consent.” It’s about time. For the past three months Senate Democrats have filibustered the nomination of Miguel Estrada to the U.S. Court of Appeals for the District of Columbia Circuit. Last week they made official their hitherto informal filibuster of the nomination of Texas Supreme Court Justice Priscilla Owen to the U.S. Court of Appeals for the Fifth Circuit. And it might not end there. In the future other nominees, including to the U.S. Supreme Court, might become filibuster targets.

Today’s hearing is a timely and much needed antidote to the rancorous politicization that has plagued the judicial confirmation process. Expert testimony will explore a number of arcane but important subjects, including the historical origins of filibusters, their purposes, the obscure Senate rules that allow them, the difference between the Senate’s executive and legislative calendar, the meaning of advice and consent, and more.

However wide-ranging the testimony, by the end of today four things should be obvious: First, the Constitution requires only a simple majority of 51 senators to confirm a judicial nomination. Second, any Senate rule or procedure — filibuster included — that allows the minority of the body to prevent the majority from consenting to a judicial nomination is in conflict with the Constitution. Third, in such a conflict, the Constitution is supreme. Thus, finally, any Senate rule that contradicts the Constitution by denying the majority its right to consent to a judicial appointment cannot stand.

No one disputes that the Senate has a legitimate role in filling judicial vacancies. The Appointments Clause of Article II, section 2 of the Constitution is clear: The president “shall nominate, and by and with the Advice and Consent of the Senate, shall appoint…Judges of the Supreme Court, and all other Officers of the United States.” To express consent senators do the obvious — they vote in favor of a nomination. And no one can dispute that the Appointments Clause requires a simple majority of 51 senators for confirmation. Elsewhere in the Constitution, when the Framers intended more than simple majorities, they said so, as they did by requiring a two-thirds majority to convict in an impeachment trial, expel a member, overcome a presidential veto, approve a treaty, or propose a Constitutional Amendment. The filibuster, which under Senate rules requires 60 votes to bring a nomination to a vote, rewrites the Appointments Clause by requiring a supermajority for confirmation. On “Meet the Press” Sen. Tom Daschle claimed that “in controversial issues [including judicial nominations] the founding fathers have said that it ought to take a supermajority to pass.” Constitutional text and more than two centuries of precedent prove Sen. Daschle wrong.

This is not to say that all filibusters raise constitutional questions. There is a long history of their use in the legislative context, and they can serve a legitimate purpose by not foreclosing debate on legislation prematurely. But in the executive context, when presidential appointments are at issue, filibustering appellate nominees is an unprecedented, though still not necessarily unconstitutional, step. If employed merely to guarantee a reasonable and limited period of debate before proceeding to an up or down vote, a brief filibuster might pass constitutional muster. But in the cases of Estrada and Owen, when the filibuster is being used not to debate, but to kill their nominations by denying the majority its right to consent to them, serious constitutional issues arise.

Yes, the Constitution permits the Senate to set its own rules. But that is hardly a blank check entitling the Senate to amend the Appointments Clause by raising the confirmation bar from simple majority to super majority, to aggrandize power by upsetting the balance between the congressional and the executive branches, and to threaten the independence of the third branch, the federal judiciary. The conclusion is inescapable. Whenever Senate Democrats, a minority of the body, filibuster judicial nominations, obstruct an up or down vote, and deny the majority its right to consent to the appointments, they subvert the Constitution.

But what is the remedy? Should the president order the Justice Department to sue Sen. Daschle and seek relief in the form of an up or down floor vote on the filibustered nominees? Or is Majority Leader Bill Frist the proper plaintiff, or the nominees themselves? While such a claim might prevail, federal courts frown on settling political disputes between the other branches, or among feuding members of the same branch. There is a simpler solution. Change the rules. That’s right. The majority could simply change the Senate rules to allow a simple majority of 51 Senators to end debate and bring a judicial nomination to the floor for an up or down vote. Although existing Senate rules require a supermajority to change them (how convenient for obstructionists), these rules are not laws, or carved in stone like the Ten Commandments. They are merely internal procedures, and under any proper understanding of the history and theory of legislative bodies, no prior Senate can exercise perpetual, dead-hand control over the present one.

It can be done without litigation, within the Senate by its own members, and it can be done immediately. Like Dorothy in the “Wizard of Oz,” who always had the power to return home but didn’t know it, Senate Republicans have always had the power to end the filibuster subversion and bring the Senate home to the Constitution. Will they do it?