Clarence Thomas

Supreme Court Associate Justice Clarence Thomas testifies on Capitol Hill in Washington, Thursday, April 15, 2010, before the House Financial Services and General Government subcommittee hearing on the Supreme Courts fiscal 2011 budget requests.

(AP Photo/Lauren Victoria Burke)

Scott Douglas Gerber is a law professor and author

Court watchers are aflutter with the news that, last Monday, U.S. Supreme Court Justice Clarence Thomas asked his first question during oral argument in a decade. Personally, I have always admired that Justice Thomas was more interested in letting the lawyers make their arguments to the bench than in trying to one-up his brethren with convoluted hypotheticals in front of a courtroom full of tourists.

But I appear to stand alone on this matter of etiquette. More specifically, seemingly every account of Monday's session has postulated that, with the recent death of Justice Antonin Scalia, Justice Thomas, as the high court's only remaining proponent of the historical approach to interpreting the Constitution, will be forced to step into Justice Scalia's shoes as the nation's leading voice on conservative constitutional theory.

Adam Liptak, The New York Time's highly regarded Supreme Court correspondent, made this point with particular poignancy: "Justice Scalia's death was a sort of passing of the baton, leaving Justice Thomas as the only member of the court fully committed to the mode of constitutional interpretation known as originalism, which seeks to apply the understanding of those who drafted and ratified the Constitution."

What has gone unmentioned to date, however, is that Justice Thomas and Justice Scalia did not share the same interpretive approach in one major category of constitutional law: civil rights. As the recent tributes to Justice Scalia have made clear, Justice Scalia was the pre-eminent figure in American law on the conservative strand of originalism that Mr. Liptak's quote describes. But Justice Thomas is not a conservative originalist on civil rights questions. Rather, he is what has come to be known as a "liberal originalist:" an originalist who places the libertarian political philosophy of the Declaration of Independence at the heart of the American conception of civil rights.

Although Justices Thomas and Scalia tended to vote together in civil rights cases, Justice Scalia declined to sign on to those portions of Justice Thomas' opinions that invoked the Declaration of Independence as the rule of decision.

To mention but two examples, Justice Scalia did not join Justice Thomas' concurring opinion in 1995's Adarand Constructors v. Pena case that found Justice Thomas quoting the Declaration at length when criticizing the federal government's use of racial preferences in awarding government contracts, and Justice Scalia did not join the section of Justice Thomas's separate opinion in 2003's University of Michigan law school admissions case that criticized the court's majority for "fail[ing] to justify its decision by reference to any principle" and that then insisted that the controlling principle -- that articulated in the Declaration -- required the case to come out the other way.

Justice Thomas wrote: "[T]he majority has placed its imprimatur on a practice that can only weaken the principle of equality embodied in the Declaration of Independence and the Equal Protection Clause. ... It has been nearly 140 years since Frederick Douglass asked the intellectual ancestors of the Law School to "[d]o nothing with us!" and the Nation adopted the Fourteenth Amendment. Now we must wait another 25 years to see this principle of equality vindicated. I therefore respectfully dissent."

Of course it can be argued that Justices Scalia and Thomas were both consistent opponents of racial preferences, and it therefore doesn't matter that one approached the issue as a conservative originalist and the other as a liberal originalist. But it would be a mistake to say it doesn't matter. Ideas matter in constitutional law: Justice Scalia was a titan on the court because of the power of his ideas about conservative originalism, not because of the results he managed to achieve.

In fact, 2008's Second Amendment case of D.C. v. Heller was arguably Justice Scalia's only significant originalist majority opinion during his entire 30-year tenure. And with the court poised to a issue a second decision this term about the University of Texas's admissions program, Justice Thomas will again have the opportunity to give voice to the libertarian idea of equality so eloquently expressed in the Declaration of Independence: People should be judged as individuals, not as members of racial or ethnic groups.

I seriously doubt that Justice Scalia's passing will transform Justice Thomas into the loquacious participant during oral argument that Justice Scalia was. But I do think that Justice Thomas's liberal originalism will come to supplant Justice Scalia's conservative originalism as the predominant alternative to the so-called progressive constitutionalism of the Court's Democratic appointees. Justice Scalia himself appeared open to the possibility: Just last term, he finally joined in full an opinion that Justice Thomas authored that invoked the Declaration of Independence.

That opinion, Justice Thomas' dissenting opinion in the same-sex marriage case of Obergefell v. Hodges, also marked the first time that Justice Thomas has appealed to the Declaration in a case that didn't involve race. Court watchers were conspicuously silent about that particular session. Perhaps they forgot that there is more to being an intellectual leader on the Supreme Court than badgering lawyers with questions during oral argument.

Scott Douglas Gerber is a law professor at Ohio Northern University in Ada, Ohio. His eight books include "First Principles: The Jurisprudence of Clarence Thomas."