This column has been updated.

Where does your morality come from?

Alan Dershowitz asked me this question several years ago, at the introductory meeting of his Harvard freshman seminar that took the centuries-old conundrum as its title. Today, Dershowitz is in the news for two reasons. The first is the president, and the second is Jeffrey Epstein.

Dershowitz has been defending Donald Trump on television for years, casting himself as a warrior for due process. Now, Dershowitz is defending himself on TV, too, against accusations at the least that he knew about Epstein allegedly trafficking underage girls for sex with men, and at the worst that he was one of the men.

Jeffrey Epstein was charged July 8 with sex trafficking crimes and pleaded not guilty. The Post's Kimberly Kindy breaks down the charges.

These cases have much in common, and they both bring me back to the classroom that day when no one around the table — not the girl who invoked Ernest Hemingway’s hedonism, nor the boy who invoked God’s commandments — seemed to know where our morality came from. Which was probably the point of the exercise.

Dershowitz’s syllabus guided us through the seminal thinkers of our times, from Dostoevsky to, well, Dershowitz. We debated torture. Is it always wrong, or should we allow it when a time bomb is literally ticking? We debated the annihilation of Hiroshima, and we debated abortion. If it’s not murder when a pregnant woman decides to have the procedure, is it murder when a man kicks her in the stomach?

We did not debate whether it’s permissible to have sex with a 15-year-old girl.

The abuse allegations lodged against the retired law professor in a current defamation suit and past complaints against Epstein have yet to be tested in discovery, let alone trial. Dershowitz has denied them vociferously for years and did so again in an interview with me. What is revealing, however, is what Dershowitz does admit. A New Yorker story by Connie Bruck this week not only ran through the charges against Dershowitz but also detailed his habit of playing “devil’s advocate” when it comes to sexual consent.

Case in point: a 1997 op-ed, in which Dershowitz suggests the age for statutory rape could be lowered, ideally to 15. He even proposes a “staircasing” system, in which penalties would go up as victims’ ages go down, from 14 to 13 to 12 and on. True, he wrote the essay 22 years ago, but Dershowitz clarified on Twitter this week that he stands by his argument, which he calls “constitutional (not moral).”

The op-ed is part of a pattern Dershowitz has used to cloak his words and deeds in philosophy, as if we were all playing around with hypotheticals in class. Sometimes, the aim is to challenge people’s thinking: “I’m an intellectual provocateur,” Dershowitz told me. Other times, it’s something bigger and better than that: to safeguard civil liberties, the core of Dershowitz’s lifelong campaign.

Maybe this calling means writing alarming columns that promote the prosecution of prostitutes but not johns, a position Dershowitz says he has since rethought. Maybe it means going on channel after channel as a volunteer lackey for Trump.

Maybe it means defending Epstein in court, as Dershowitz did when the feds first knocked in 2005. Dershowitz famously has represented accused rapists and wife-killers aplenty, justifying this personal speciality by stressing that everyone deserves a defense. He takes the principle to the extreme, almost as if he were seeking out clients each more odious than the last. (After this column was published online, Dershowitz wrote to point out that he has represented many more female clients, including victims of violence, than men accused of assaulting or killing women.)

Really, each of these things is as much of a moral matter as those we once mulled over as first-year students. In fact, they raise more serious questions of ethical conduct than whether you’d theoretically push a man over a bridge to stop a trolley from killing five innocent kids. Because life is not a college seminar.

Principles are important, but they can also be a distancing mechanism that permits us to maintain an aura of rectitude even as we go around behaving in ways that aren’t right at all. They can allow us to absolve ourselves for our actions by claiming they’re in service of some metaphysical lodestar that supersedes any effect on real people in real life. Sometimes, we’re simply wrong — not just constitutionally, or legally, but ethically, too.

You can make a convoluted argument that investigations of the president constitute irresponsible congressional overreach, but contorting the Constitution is your choice, and the consequences to the country of your contortion are yours to own, too. Everyone deserves a defense, but lawyers in private practice choose their clients — and putting a particular focus on championing those Dershowitz calls the “most unpopular, most despised” requires grappling with what it means for victims when an abuser ends up with a cozy plea deal.

When the alleged abuser is your friend Jeffrey, whose case you could have avoided precisely because you have a personal relationship, that grappling is even more difficult. Maybe it’s still all worth it to keep the system from falling apart, because next time it might not be a billionaire financier who wanted to seed the human race with his DNA on the stand, but a poor teenager framed for a crime he didn’t commit.

Dershowitz once told the New York Times he regretted taking Epstein’s case. He told me, “I would do it again.”

Now the defense lawyer is defending himself, and the jury needs instructions. There’s an answer to the question none of us students could reach all those years ago: Your morality comes from what you do.

Twitter: @mollylroberts

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