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For the first time in nearly seven years last week, Justice Clarence Thomas spoke up during oral arguments.

To those in the court room it seemed clear that he had cracked a joke. But no one knew exactly what he had said. The court transcript was inconclusive because the reporter was unable to pick up the justice's words amid laughter from the bench.

But today, the mystery is solved. Alderson Reporting, the company that transcribes all oral arguments, listened to the audio and determined that Thomas cracked a joke at the expense of … wait for it … Harvard Law School.

The justices were discussing the qualifications of lawyers who had been assigned to a murder case when Justice Antonin Scalia asked Carla S. Sigler, the assistant district attorney of Louisiana, about one of the lawyers.

"She was a graduate of Yale Law School?" Scalia asked.

Sigler responded, "She's a very impressive attorney."

Then Scalia talked about another lawyer, who was a graduate of Harvard Law School.

"Son of a gun!" joked Scalia, a Harvard Law graduate himself - class of 1960.

To which Thomas, a 1974 Yale law graduate, said into the microphone, "Well, there, see: He did not provide good counsel."

Pa dump pa.

To laughter, Sigler responded, "I would refute that, Justice Thomas."

The transcript revealed that there was plenty of cross talk and laughter between the justices. At one point, Justice Sonia Sotomayor said, "Counsel, do you want to define constitutionally adequate counsel? Is it anybody who's graduated from Harvard and Yale?"

The transcript indicated her comments were followed by laughter.

The Justices then got back to the very serious case at hand.

It is not as if Thomas never speaks up in the courtroom. When he reads his opinions, his rich baritone voice fills the chamber.

Over the years, he has offered various reasons for not questioning lawyers during oral arguments including a desire to let the lawyers have enough time to present their arguments.