The battle over President Bush's judicial nominees will get much more heated Wednesday evening. That's when Senate Republicans launch a round-the-clock "Justice for Judges Marathon" on the Senate floor.

It's set to peak Friday morning with votes to try to end Democrat filibusters (search) of three nominees, followed by a vote to change Senate rules for ending such filibusters. With C-SPAN rolling, the aim is to fire up the base for next year's political season-and longer range, to begin educating the public about an often obscure set of issues.

Polls show that the judiciary (search) is the least understood branch of government. And that goes for how judges are selected as well. Let's start with that. The Constitution gives the president the power to nominate judges, with the advice and consent of the Senate. By implication, Senate consent means by a majority. When the Constitution requires more than a majority-to ratify treaties, for example-it says so. For everything else, decisions are by a majority. Therein lies the current problem.

After Democrats lost control of the Senate a year ago, they invoked the Senate's arcane filibuster rules to debate to death nominees said to be "outside the mainstream." Because it takes 60 votes under current rules to end a filibuster, that amounts to imposing an extra-constitutional supermajority hurdle for nominees. And that's why Republicans are crying foul-the way the filibuster is being used today is unprecedented. Although Senate majorities are voting to end the filibusters--the votes are likely there to confirm, that is--the filibuster rules are being used to prevent a direct up-or-down vote on the nominations. Thus, the cry from Republicans: "Vote 'em up, vote 'em down, but give 'em a vote."

Now let's get to the heart of the matter. What's going on here is payback-in spades. Yes, a Republican Senate sat on some of President Clinton's nominees, many sent too late to be confirmed, others ignored because their records showed them to be true judicial activists (search) with little regard for the rule of law. The seminal event in this battle, however, was the 2000 presidential election and its potential for shaping the courts far into the future. When the U.S. Supreme Court effectively decided the outcome by overturning a lawless Florida Supreme Court, Democrats went to the barricades.

They got a break in May 2001 when Vermont Sen. James Jeffords (search) became an Independent, giving them control of the Senate. That's when the Senate Judiciary Committee (search) began stalling on the president's nominees. And New York's Charles Schumer (search) upped the ante by calling for hearings not on the nominees but on the role "ideology" should play in the Senate's confirmation decisions.

Democrats focused on the crucial appellate courts (search). (That's why their cry today that the Senate has confirmed more Bush judges than ever is disingenuous. It lumps in the far more numerous district court judgeships.) As Americans were voting last year, eight of Bush's first 11 appellate court nominations, announced in May 2001, still hadn't had even a hearing, to say nothing of a committee or a floor vote. When Democrats lost the Senate after the 2002 election, they switched from stall to filibuster. And that's where we are today. They've filibustered four appellate court nominees, put "blue slip" holds on others, and more is promised.

The complaint that those nominees are "outside the mainstream" is closely tied to Schumer's focus on "ideology." In fact, Schumer spelled out his thinking in a June 2001 New York Times op-ed. The Senate should block nominees, he said, whose values are outside "the core values held by most of our country's citizens."

Judgments about that would be better made, one imagines, by members of the majority party, yet Schumer confidently presumes to judge from his minority post. What especially disturbs him, however, are "the Supreme Court's recent 5-4 decisions that constrain congressional power." The idea that the Constitution might constrain Congress is apparently too much to bear.

And so we come to the nub of the matter. For too many Democrats, the courts are something akin to another legislative branch. Party elder Joseph Califano (search), from the Carter cabinet, gave it away in an August 2001 Washington Post op-ed entitled "Yes, Litmus Test Judges." We've learned, he wrote, "that what can't be won in the legislature or executive may be achievable in a federal district court where a sympathetic judge sits." Not a judge, applying the law, but a "sympathetic" judge. That's politics, not law. I for one don't care whether the judge before me is or is not "outside the mainstream." I do care whether he knows the difference between politics and law--and respects it.

Roger Pilon is vice president for legal affairs at the  Cato Institute and director of Cato's Center for Constitutional Studies.