After Justice Stephen G. Breyer spoke to students at Lowell High School in San Francisco earlier this month, the wire service story reported that he had talked about “how laws are made at the nation’s highest court.”

The conservative blog ConfirmThem.com erupted in constitutional indignation at Breyer’s apparent confession to going beyond the Supreme Court’s legitimate powers. The outcry petered out two days later, however, after the blog’s moderator, Andrew Hyman, acknowledged that a videotape cleared Breyer of claiming any extra constitutional power to write laws.

The misapprehension still provides a good occasion to examine what has now become the mantra of conservative critics of the judiciary: that judges forget their place in the constitutional order by “legislating from the bench.”

Like the companion criticism of “activist judges,” this slogan usually means nothing more than disagreement with the judicial decision under consideration. But if it has any real meaning, the slogan reflects an oversimplified and fundamentally misleading view of the judicial role.

In fact, judges routinely make law on the bench. Their jobs demand it even when legislative bodies function at their best. And judges are often called on to clean up the mess after legislative bodies do their jobs badly — for example, by writing sloppy statutes, ducking hard issues or falling into political gridlock.

Take this simple case: Congress wrote a law saying that the Postal Service can’t be sued for “negligent transmission” of mail. A postal patron filed a slip-and-fall suit after she stumbled over a pile of packages left on her porch. The Postal Service said the law barred her suit, but the Supreme Court decided last week that leaving a stack of mail on the porch was not what Congress meant by “negligent transmission.” Straightforward, yes, but one justice disagreed.

The court heard arguments last week on a trickier statutory issue: whether the Clean Water Act’s protections for “the waters of the United States” extend to wetlands separated either by distance or man-made barrier from recognizable waterways such as rivers or lakes. At first blush, that might seem a stretch. But the water in the wetlands has to go somewhere. So Congress’ purpose in passing the law might be frustrated if the term is defined narrowly. The justices appeared to be closely divided on the question.

In both cases, Congress did a fairly good job of lawmaking. Even the best legislative drafters can’t anticipate all the possible issues. So courts have to decide. That’s all the more true when Congress is rushed — as when it cleared, on Sept. 14, 2001, the law authorizing military force against anyone connected with the terrorist attacks of three days before.

Does the law, which is very short on specifics, allow the president to detain a U.S. citizen as an enemy combatant and deny him any kind of hearing? That’s how President Bush read it. A closely divided Supreme Court gave Bush the first point but ruled that some kind of hearing was required. Now, Bush says the same law also gives him the authority to wiretap U.S. citizens without a warrant if they’re talking with suspected terrorists overseas. Congress never even thought about that question, it would seem. The Supreme Court may have to decide — though probably not anytime soon.

Cases with confusing draftsmanship pop up on the court’s docket all the time, forcing the justices to choose between what’s written and what makes sense. The cases go both ways. At other times, Congress writes with a broad brush — think of the statutory requirement that broadcasters operate in the “public interest, convenience and necessity” — and lawmakers hope that agencies and courts can provide more specific meaning.

And sometimes Congress does nothing at all, even though it needs to. Courts have been inundated with asbestos claims for the past 30 years. They have managed as best they can, but the Supreme Court itself has called on Congress to write some sort of national compensation scheme. But Congress can’t break the interest-group gridlock on the issue. So courts have to keep trying.

The conservative critics’ biggest gripe, of course, is with decisions by the federal courts that hold state or federal laws unconstitutional. But they invoke their critique selectively to suit their own policy preferences. They denounce judges for “legislating from the bench” on abortion rights or gay marriage. But they are even more livid about the Supreme Court’s decision in June 2005 upholding the Connecticut law that allowed the city of New London to seize private property for purposes of economic development. In that instance, apparently, the justices needed to “legislate from the bench.”

In their confirmation hearings, Chief Justice John G. Roberts Jr. and Justice Samuel A. Alito Jr. both assured the Senate that they viewed the Supreme Court’s role as a modest one. Surely, both meant what they said. But just as surely, they will be “making law” on the high court. As Chief Justice John Marshall wrote 200 years ago, “It is emphatically the province and duty of the judicial department to say what the law is.”

Kenneth Jost is the Supreme Court editor for CQ Press.