Justice Thomas, on the other hand, cited only a single author, and then only by way of contrast. “It’s not a mystery novel,” he said of a good brief. “People can’t think, ‘I’m Agatha Christie,’ or something like that.”

He said his own style was accessible to everyone, a point that is open to dispute. Consider, for instance, the opening sentence of his most recent opinion: “The False Claims Act (FCA), 31 U.S.C. §§3729 — 3733, prohibits submitting false or fraudulent claims for payment to the United States, §3729(a), and authorizes qui tam suits, in which private parties bring civil actions in the government’s name, §3730(b)(1).”

In the interview, Justice Thomas provided evidence that his writing is easy to grasp, including a remembered airport encounter with a man he assumed to be a law enforcement official.

“He looked like a deputy sheriff,” Justice Thomas said. “He had a little midriff going.”

“Here’s a guy,” the justice went on, “who looked like he clearly didn’t go to college, who said that ‘I’ve read all your opinions.’ Well, that’s accessibility.”

The interviews were conducted by Bryan A. Garner, the president of the legal-writing company, LawProse. Mr. Garner, the editor of Black’s Law Dictionary, has written a book on “the art of persuading judges” with Justice Antonin Scalia, and the two are at work on a sequel.

The justices generally said the briefs submitted to the Supreme Court were of high quality but too long. The briefs, which are presented in plump printed booklets, can contain up to 15,000 words, and many advocates use almost every one. “Lawyers somehow can’t give up the extra space,” Justice Ginsburg said, “so they fill the brief unnecessarily, not realizing that eye fatigue and even annoyance will be the response they get for writing an overlong brief.”