Footnote Two was Thurgood Marshall’s warning to the nation of the juridical juggernaut he believed the aggressively conservative majority was about to launch. The note came last June in Marshall’s final, angry dissent as a justice–after his brethren had scuttled their fifth precedent in a matter of months. Marshall compiled a list of “endangered precedents” that he said might be hunted down by the activists on Chief Justice William Rehnquist’s court. On the list were those closely decided cases won by the liberals just a few years earlier. Civil rights, free speech, criminal safeguards–all these were in danger now that the Reagan-Bush justices were at the helm. That right-wing majority, Marshall wrote, “sends a clear signal that scores of established constitutional liberties are now ripe for reconsideration.”

As the high court opens its 203d term this week, Marshall’s prediction starts coming to the test. Jurisprudential change is typically glacial, so the court is unlikely to effect a conservative revolution overnight. But the current docket presents the justices with many opportunities to discard doctrine they don’t like from the eras of Chief Justices Earl Warren and Warren Burger. If Clarence Thomas is confirmed (box) his arrival is likely only to accelerate the urge to purge past decisions. Why? It takes five votes to win. Rehnquist and Justice Antonin Scalia are the steam engines of activism, but they need help. Thomas would give them yet another potential ally on a court with no diehard liberals and but two moderates. Among the possibilities for constitutional temblors:

The court will consider whether state laws prohibiting cross burning and other “hate speech” violate the First Amendment. The case, arising from an ordinance in St. Paul, Minn., may give the justices a chance to cut back on two recent flag-burning decisions, both upholding by a 5-4 margin a protester’s First Amendment rights. Liberals Marshall and William Brennan Jr., who voted with those majorities, have since retired. Moreover, last term’s ruling that nude dancing could be banned suggests a court sympathetic to community sentiments. In another case, the justices will decide whether crime may pay. Are “Son of Sam” laws, which require criminals to give up the proceeds from writings or movies about the crime, inconsistent with free speech? The specific dispute involves convicted ex-mobster Henry Hill, whose story was told in “GoodFellas.”

For a generation, conservatives have complained about judicial supervision of state institutions that have violated federal law. On the first day of the term, Georgia’s DeKalb County school district will try to convince the court that 22 years of oversight is enough, even though segregation remains in its system due to demographic shifts. Similarly, Boston officials will be seeking release from a federal decree prohibiting jail overcrowding.

The most likely target for precedent busting is a 1971 decision erecting a tall wall between church and state. The Bush administration wants constitutional standards relaxed so only coerced participation in religious activities is barred. The lawsuit centers on a rabbi’s nondenominational prayer at a public-school graduation ceremony in Rhode Island.

The justices have not yet accepted any cases challenging Roe v. Wade, the 1973 ruling creating the right to abortion. There are several cases working their way through lower courts that could reach Washington by spring. Meantime, the justices will have to decide if anti-abortion blockades, like the kind used by Operation Rescue in Wichita, Kans., violate a woman’s civil rights.

Only half the court’s calendar has been filled, so the justices have time to add cases on affirmative action and defendants’ rights, both prime targets for conservative incursions. It is a heady time for the right, finally rid of judges like Brennan, Marshall, Hugo Black and William O. Douglas who dominated the Supremes for so long. Yet it is a risky time for the court as an institution. Winning is one thing, legitimacy quite another. The judicial activists would do well to remember the New Deal era. In one five-year stretch, the court tossed aside 29 previous cases. In a 1944 dissent, Justice Owen Roberts dryly observed that these decisions “bring adjudications of this tribunal into the same class as a restricted railroad ticket, good for this day and train only.”

Or consider Jay Leno. “You know, it’s almost time to turn back the clock,” he joked on “The Tonight Show” last week. “That’s right, the Supreme Court’s back in session. " Pretty funny. But when the court becomes fodder for the monologue, you know it’s time to start wondering about its reputation.