A week ago, I pondered whether public-school integration was dead. I got my answer Monday as I sat in the audience listening as the nine justices of the U.S. Supreme Court probed and prodded on the matter of race.

Diversity, as a tool of public education, is dead as a doornail.

It was in the air. The elegantly gilded courtroom turned somber as one justice after another dismissed the notion of purposeful diversity efforts in public education.

Someone next to me whispered they had just seen the widow of former Supreme Court Justice Thurgood Marshall. As a young attorney, Marshall successfully argued the landmark Brown v. Board of Education case that paved the way for federal troops to escort black children past angry crowds into newly integrated schools.

It seemed strangely appropriate that Marshall's widow be there Monday to witness the unraveling of Brown.

The court won't rule on Parents Involved in Community Schools v. Seattle School District until spring. But I believe a narrow majority will ban Seattle's use of race in divvying up seats in oversubscribed high schools.

The death of the racial tiebreaker will not be the end of the world. It was a diversity tool less than artfully applied. Students could self-identify their race, opening a loophole large enough for hordes of crafty parents to pass through over the years. A smart, perceptive school board ought to be able to find other ways to compel diversity in neighborhood schools that are growing less diverse.

However, if the court turns Brown on its head by prohibiting any consideration of race in public education, narrowly tailored or not, we're in trouble. It would be an almost perverse interpretation of the 14th Amendment's equal-rights clause. Instead of recognizing the necessary use of racial groups, particularly when ensuring equal opportunity in education, the court could well adopt a colorblind mentality.

Justice Anthony Kennedy is the likely swing vote and is thought to be leaning toward ruling against Seattle. But — and I may be as naively optimistic as the little boy looking for a horse in the manure pile — I believe he is conflicted.

On Monday, Kennedy was first out the gate with a bevy of questions designed to clarify the difference between race-conscious objectives and racial actions. Lawyers for PICS, the parent group suing the district, said the U.S. Constitution prohibits it all.

But Justice Antonin Scalia, perhaps angling for wiggle room in the ruling, jumped in to ask if such a strict view meant magnet schools and other voluntary diversity systems were also unconstitutional.

The PICS attorney argued that such hypotheticals aren't necessary to ponder for the court to rule.

Enter Kennedy. "Well, it may not be necessary for you, but it might be for us when we write the case."

Kennedy later made his conflict clear. "Assuming some race-conscious measures are permissible to have diversity, isn't it odd to say you can't use race as a means?" he asked the PICS attorney. "You just don't want to embrace that contradiction," he said.

Justice Stephen Breyer, addressing the solicitor general, referred to a 1971 Supreme Court case known as Swann v. Board of Education.

"In Swann, the court said that a school board 'could well conclude that to prepare students to live in a pluralistic society each school should have a prescribed ratio of Negro to white students reflecting the proportion of the district as a whole.' That's more radical than anything we have here," Justice Breyer said, referring to the two integration cases before the court Monday.

"Thousands of school districts across the country have relied on (Swann) when trying to bring about a degree of integration," Breyer said. "What are you telling this court is going to happen when we start suddenly departing from that case?"

I take it we're about to find out. For the sake of Seattle's students, struggling to learn in schools of uneven quality, I hope the Seattle School Board has a Plan B.

Lynne K. Varner is a columnist for the Seattle Times. Reach her at lvarner@seattletimes.com.