When the Affordable Care Act had its day in front of the Supreme Court, the “highlights” consisted of two things: the content of the questions the justices asked during the oral arguments, and the answers the respective litigators gave. And then there was the one anti-highlight: Clarence Thomas remained silent during in this case, matching a record of silence so persistent that a computer program that matches sound recordings of oral arguments with specific justices was unable to identify Thomas because they didn’t have a large enough sample of his voice.

And so, in a lecture given recently at the University of Kentucky, Thomas defended his silence and chided his fellow justices:

“We have a lifetime to go back in chambers and to argue with each other,” he said. “They have 30, 40 minutes per side for cases that are important to them and to the country. They should argue. That’s a part of the process….I don’t like to badger people. These are not children. The court traditionally did not do that. I have been there 20 years. I see no need for all of that. Most of that is in the briefs, and there are a few questions around the edges.”

What is interesting here is not that Thomas is more or less right on the substance — the Justices get thousands of pages of briefs, staffs of clerks to guide them through the material, and then often end up arguing with each other for only about 10 minutes on the most contentious cases. When justices have such clearly defined political, ideological, and jurisprudential commitments as our current Court does, this should not be at all surprising.

But what’s interesting is not only how Thomas is correct in seeing questions during oral arguments as largely pointless, his own silence has not at all impeded his own influence in the court. One of the more insightful parts of Jan Crawford Greenburg’s Supreme Conflict is her argument that Thomas is both an original and independent actor in the Court (i.e. not Scalia’s lackey), but that he’s been very influential among his fellow justices. She made this particular argument in a Wall Street Journal op-ed she wrote in 2007:

Consider a criminal case argued during Justice Thomas’s first week. It concerned a thief’s effort to get out of a Louisiana mental institution and the state’s desire to keep him there. Eight justices voted to side with the thief. Justice Thomas dissented, arguing that although it “may make eminent sense as a policy matter” to let the criminal out of the mental institution, nothing in the Constitution required “the states to conform to the policy preferences of federal judges.”

After he sent his dissenting opinion to the other justices, as is custom, Justices Rehnquist, Scalia and Kennedy changed their votes. The case ended up 5-4.

Justice Thomas’s dissents persuaded Justice Scalia to change his mind several times that year. Even in Hudson v. McMillan, the case that prompted the New York Times to infamously label Justice Thomas the “youngest, cruelest justice,” he was again, initially, the lone dissenter. Justice Scalia changed his vote after he read Justice Thomas’s dissent, which said a prison inmate beaten by guards had several options for redress–but not under the Eighth Amendment’s prohibition of “cruel and unusual punishment.”

From the beginning, Justice Thomas was an independent voice. His brutal confirmation hearings only enforced his autonomy, making him impervious to criticism from the media and liberal law professors. He’d told his story, and no one listened. From then on, he did not care what they said about him.

Clarence Thomas, for example, is the only justice who rarely asks questions at oral arguments. One reason is that he thinks his colleagues talk too much from the bench, and he prefers to let the lawyers explain their case with fewer interruptions. But his silence is sometimes interpreted as a lack of interest, and friends have begged him to ask a few questions to dispel those suggestions. He refuses to do it. “They have no credibility,” he says of critics. “I am free to live up to my oath.”

But the forcefulness and clarity of Justice Thomas’s views, coupled with wrongheaded depictions of him doing Justice Scalia’s bidding, created an internal dynamic that caused the court to make an unexpected turn in his first year. Justice O’Connor–who sought ideological balance–moved to the left. With the addition of Chief Justice John Roberts and Associate Justice Samuel Alito, the court now is poised to finally fulfill the hopes of the conservative movement. As George W. Bush told his legal advisers early in his presidency, he wanted justices in “the mold of Thomas and Scalia.” Interestingly, on President Bush’s marquee, Justice Thomas got top billing.

And as the Court might very well be on the verge of striking down a Democratic president’s expansive effort to regulate a key sector of the national economy and expand the social safety net, Thomas’s originalist-libertarian worldview might be at its most influential. And he barely had to say a word.