Adam Liptak in the NYT:

Mr. Feldman conducted an extensive analysis of overlapping language, using anti-plagiarism software to detect similar wording in briefs and opinions from 1946 to 2014. The study and related findings were based on almost 10,000 briefs and looked for passages of at least six words with an overlap of at least 80 percent.

Justice Thomas’s majority opinions had the highest rate of overlaps with language in parties’ briefs in the decade since Chief Justice John G. Roberts Jr. joined the court.

Paul M. Collins Jr., a political scientist at the University of Massachusetts, Amherst, who helped conduct two more limited studies that came to similar conclusions, said there might be a link between Justice Thomas’s approach to arguments and the high rates of seemingly borrowed language in his opinions.“His lack of engagement in oral arguments suggests that he doesn’t find them especially useful,” Professor Collins said. “If this is true, his view of cases is being heavily shaped by the legal briefs filed in the cases.”

Justice Thomas is often more expansive when not writing for the majority. In the last term, he filed 30 dissents and concurrences, more than any other justice. Many concerned major constitutional questions, were longer than the majority opinions they critiqued and made novel points.

Over the years, the average rate of nearly identical language between a party’s brief and the majority opinion was 9.6 percent. Justice Thomas’s rate was 11.3 percent. Justice Sonia Sotomayor’s was 11 percent, and Justice Ruth Bader Ginsburg’s 10.5 percent. All three sometimes produce institutional prose.

In response to my tweeting a link to this piece, Judge Michael Smyth tweeted (in a tweet since deleted) questioning whether the focus on Justice Thomas was fair, given the close rates for Justices Sotomayor and Ginsburg.