Federal appellate judge Richard Posner’s decision to retire should surprise no one who’s read his latest book. Posner, of Chicago’s Seventh Circuit, is pushing 80, which he suggests is when judges should retire, and in The Federal Judiciary: Strengths and Weaknesses, he shows little concern over alienating his superiors. The job of appellate judges involves writing opinions that the Supreme Court, should it review them, will admire and concur with, but Posner sounds beyond caring. He devotes half his book to the court and vastly more space to its weaknesses than its strengths. “I think the Court is at a nadir,” he writes. “I don’t think it’s well managed and I don’t think the Justices are doing a good job.” He concedes that it’s “impertinent” to say so.

Posner names names. One is Chief Justice John Roberts, whom he holds in low regard. “What can Chief Justice Roberts have been thinking?” Posner wonders, picking apart Roberts’s dissent from the 2015 ruling that found same-sex marriage constitutional. “Of course I have no idea what he was thinking. I’m not sure he did either. . . . Roberts committed a further error. . . . The Chief Justice’s biggest error. . . History seems not to be the Chief Justice’s strong suit.” At his confirmation hearing, Roberts famously compared a judge to a baseball umpire calling balls and strikes. Posner calls this comparison “absurd” and notes that umpires don’t decide at the end of the game who won it.

Posner is just as contemptuous of Roberts’s majority opinion in the 5-4 decision in 2015 that gutted the Voting Rights Act. “Faced with an insuperable hurdle,” Posner writes, “Roberts ingeniously but unscrupulously invoked what he called a ‘fundamental principle of equal sovereignty’ among the states.” It’s a principle that, at least as applied by Roberts, Posner thinks doesn’t exist.

Posner calls himself a judicial “pragmatist.” A blunt way to put this is to say that a ruling is never right when it’s absurd. Here’s an absurdity: the notion that proof of your innocence might not be enough to save you from being hanged. Yet that’s what the late justice Antonin Scalia thought. “What civilized principles,” Posner muses, “could lie behind his rejection of a constitutional right—easily derived, one might think, from the cruel and unusual punishments clause of the Eighth Amendment—to judicial consideration of proof of innocence discovered after a defendant had been convicted of murder and sentenced to death but before he’d been executed? Scalia’s view was that as long as the trial and the sentencing hearing had been procedurally regular, an innocent defendant could lawfully be executed. . . .

“I’d like to see his encomiasts, liberal or conservative,” Posner goes on, “defend that position and the moral outlook that lay behind it.” Perhaps, he dryly suggests, Scalia, as a devout Catholic, was content to believe an innocent man put to death would receive “divine clemency.”

Since the two former University of Chicago colleagues had a falling out late in Scalia’s life, Posner has delighted in mocking him. Scalia fancied himself an “originalist,” Posner notes, and to give us an idea of where that notion took him, writes that Scalia held flogging to be constitutional because it was commonplace when the Bill of Rights was written in the 18th century. Originalism denies the obvious—which is that “the Constitution and many of its amendments are obsolete,” Posner the pragmatist argues, and besides, Scalia was actually all over the map.

Posner’s book is impregnated with his disdain for Scalia’s jurisprudence. He begins his long first chapter on the Supreme Court by ridiculing the posthumous tributes to Scalia from people who should have known better, and surely did. For instance, the “mawkish” salute by Justice Elena Kagan, who said Scalia would “go down in history as . . . one of the greatest.” The adoration of the law clerk who said Scalia “had a contagious laugh that spread pure joy.” (Posner said he knew Scalia for nearly 40 years yet never caught that infection.) The dumbfounding assessment of professor Cass Sunstein that Scalia had been “one of the greatest justices in the Court’s history, and among its three best writers.” Posner doesn’t simply shrug this off as hyperbole; he confronts Sunstein with a list of justices Posner thinks wrote a lot better. They include not only Roberts (he’ll soon tell us what he thinks of Roberts) but Roberts’s predecessor as chief justice, William Rehnquist, whom Posner elsewhere in the book calls a “genuine sourpuss” and “altogether a strange bird.”

And at the far end of Posner’s long book, Scalia is still central to his thoughts. In his epilogue Posner gives Scalia credit for the sense of humor and writing style he’d disparaged earlier, and for his “surprising concern” for the rights of defendants. That said, Scalia was an “emphatic believer in the devil” and “implicitly rejected evolution” in favor of the biblical account of Adam and Eve. But Posner makes it clear that his problems with the justices weren’t limited to Scalia alone: “I am equally or more critical of some of his colleagues,” he acknowledges, among them Roberts, Kagan, and Samuel Alito.

As for Clarence Thomas, apparently he was too soft a target for Posner to waste bullets on. Posner simply identifies him as the justice who, after Scalia, now wears the “mantle of judicial ultraconservatism,” and turns the task of evisceration over to the law professor Eric Segall. Posner quotes at length from a Segall article whose thrust is declared by its title, “Justice Thomas’ 25 Years of Constitutional Politics Not Law.”

Five years ago, writing the first of several columns on the enmity between Posner and Scalia (for others, see below), I said that posterity was likely to remember Posner, though outranked by Scalia, “as the more important jurist; his opinions are anthologized in law school casebooks more frequently than the opinions of any other living judge on any court.” I suspect Posner believes that he, not Scalia, should be remembered as the verbal giant: after all, he’s written close to 40 books (the number depends on how you count various editions of some). And they’re consequential books. One of them, Sex and Reason, published in 1992, won a literary award in a competition I helped judge, being about sex without making sex embarrassing and law without making sex a bore.

Though it can be argued that it was Scalia who inspired Posner to really hit his stride.