In a series of essays published in 1998 under the title Sexual McCarthyism, he criticized Starr for a series of leaks—“really hemorrhages,” he wrote—and questioned whether Starr needed to be investigated by an independent counsel. He pointed to the strong appearance of a conflict of interest in his connection to conservative activist Richard Mellon Scaife, who Dershowitz described as a “Clinton-basher” and who’d recently endowed a new school of public policy at Pepperdine University, of which Starr was named the first dean in 1996. (Starr withdrew without taking office after the Lewinsky controversy but later became dean of the law school.) “Starr,” wrote Dershowitz in an essay from the book dated May 1996, “is quickly destroying the credibility and integrity that alone justifies having an Independent Counsel.”

Later, Dershowitz painted Starr in even darker terms, as a threat to democracy. “Which is more dangerous to our liberties,” Dershowitz asked in a 1998 essay, “a president who may have had a sexual encounter with a willing intern and then tried to cover it up? Or a prosecutor who may have leaked secret grand jury testimony in an effort to get potential witnesses to change that testimony, and who hid his conflict of interest from the court?” Dershowitz concluded, “Most Americans correctly believe that the allegations against Kenneth Starr are far more serious, and his alleged misconduct—if it occurred—far more dangerous to our liberties.”

As uncomfortable as the pairing between Dershowitz and Starr may be, their individual decisions to represent Trump are even more confusing and problematic. Both men are zealous lawyers who have crafted serious moral narratives around the purpose of their life’s work—and both of them will be hard-pressed to reconcile these accounts with the decision to sit in front of the Senate, and all of America, in defense of Donald J. Trump. It’s the latest, and perhaps the most compelling, example of how people’s core principles are bent, and sometimes abandoned, in the distorting field of Trump’s gravity.

For Starr, the challenge will come from reconciling the current Republican position that no additional witnesses should be called during the Senate trial with the position he took in the 1990s, when he was rationalizing the fact that his real-estate corruption investigation had transmogrified into a perjury inquiry on an unrelated civil matter. Back then, Starr defended the idea of turning over every conceivable stone to find evidence of wrongdoing: “Lawyers,” he told the Mecklenburg Bar Foundation in 1998, “have a duty not to use their skills to impede the search for truth.”

This horrified Dershowitz, who saw Starr’s yearslong pursuit of Clinton as the quintessential example of overreach. Of all Dershowitz’s criticisms of Starr, he reserved the harshest for this argument. “He regards his ‘search for truth’ as an end that justifies any means,” Dershowitz wrote of Starr in an essay titled “Starr Above the Law.” “So did those who conducted the Inquisition and the Star Chamber. He urges lawyers to be ‘guided not simply by the client’s interests’ but by society’s interest as well.” Dershowitz concluded: “This is what Stalin expected from Soviet lawyers.”

On Dershowitz’s part, the representation of Trump carries the whiff of a different kind of hypocrisy. That’s not because Trump is a Republican or because he’s accused of serious misconduct. Dershowitz, a Democrat, has made a specialty of representing even the most unpopular defendants—especially the most unpopular defendants—in the interest of making the point that everyone deserves fair treatment. As a civil libertarian, I’m a longtime admirer of Dershowitz’s work and writing; if he were representing Trump at a criminal trial, I’d defend both the necessity of the defense and its consistency with Dershowitz’s life work.

But this is not a criminal trial. It's a political proceeding. Here, Dershowitz is operating as an expert on constitutional law, not a civil libertarian, a fact he has acknowledged. In a statement released on Twitter, Dershowitz said he is “participating in this impeachment trial to defend the integrity of the Constitution and to prevent the creation of a dangerous constitutional precedent.” Later, he told the New York Times, “I’m presenting an independent argument as an independent academic against impeachment, which is a view I’ve held for a long time.”

Few people are as concerned with the consistency of their intellectual legacy as Dershowitz is. When I interviewed him for a POLITICO Magazine profile in 2018, he told me, “I try to be consistent with my principles.” We spoke about trying to think about justice from the standpoint of the philosopher John Rawls’ “original position”—that is, what we would think was fair without knowing whether we were Democrat or Republican, black or white, rich or poor. It’s how Dershowitz gets to a place where he can say, as he told me, “If Hitler were to call me today, saying he’s in the jungles of Brazil, I would defend him—very reluctantly,” and it’s this consistency that’s at the heart of what’s admirable about his career.

It’s going to be difficult, if not impossible, for Dershowitz to reconcile the constitutional argument that he’s about to make with his past work. In his writings about Starr, Dershowitz took a clear position on what constituted valid grounds for impeachment. “What kinds of offenses warrant the extraordinary remedy of legislative removal of a President?” he mused in his 1998 book. “The answer must be an offense that poses a clear and present danger to our body politic—a high public violation of official duty.” The impeachment proceedings against Richard Nixon were proper, Dershowitz argued. “His crimes went to the essence of what an impeachable offense should be: he subverted the Constitution to his own partisan benefit, and in the process endangered the liberties of all Americans.”

It’s difficult to imagine an argument that Donald Trump’s use of American foreign aid for his own partisan benefit and the ensuing cover-up isn’t at least as serious, from a constitutional perspective, as the Watergate burglary and its ensuing cover-up. Moreover, Dershowitz won’t be cross-examining anyone, since he has said he’s participating solely as a constitutional scholar. He’ll need to deal with the facts as alleged, which means defending the activity as it took place.

Perhaps he could say he has reconsidered Watergate. Perhaps he could say Trump’s abuse of power wasn’t as serious as Nixon’s and that, while serious, isn’t enough to merit impeachment. But that argument wouldn’t please his client very much. Trump put the kibosh on Republicans who wanted to concede that the Ukraine affair was improper but didn’t rise to an impeachable level. Trump, of course, insisted his behavior was perfect.

It thus feels inevitable that, whichever side you’re on, another hero is about to fall in service of Trump. Starr, who has rejected the role of government lawyers as partisans, instead zealously advocating their role as seekers of truth, is about to argue that the Senate trial should exclude additional fact witnesses with material information. And Dershowitz, who correctly concluded that Nixon’s subversion of democracy merited impeachment, seems about to argue that the far more serious behavior of the current president does not.

For both men, the impeachment trial threatens to taint with hypocrisy a long, distinguished career. But Trump’s power seems to have a special pull, and the allure of public attention is difficult to resist. Apparently Starr, 73, and Dershowitz, 81, would rather bask once more in its glow than go gentle into that good night.