[Jonathan Zimmerman teaches history and education at New York University. He is the author of “Innocents Abroad: American Teachers in the American Century” (Harvard University Press).]

About thirty years ago, I sat in a musty college lecture hall and heard a statement that has stayed with me ever since. “The most important thing you’ll learn from history,” the professor said, “is that victims are not always angels.”

I thought of the remark last week, as I read about the ugly denouement to the rape case against three Duke University lacrosse players. Local district attorney Michael B. Nifong resigned and gave up his law license, shortly before an ethics panel charged Nifong with “dishonesty, fraud, deceit, and misrepresentation” in his prosecution of the case. Nifong still might face criminal penalties or civil lawsuits from the three players, who were cleared of all charges earlier this year.

If the panel’s report is correct, Nifong deserves everything he gets—and more. The panel found that Nifong played up the racial dimensions of the case—three white men accused of raping a black woman—in order to win a tight election. Worst of all, he misled defense lawyers and a judge about DNA evidence that could have absolved the accused students.

So the students are clearly the victims here, railroaded by a devious prosecutor with a political axe to grind. But that doesn’t make them angels, as my professor would have warned. These kids didn’t break the law, but they did behave like fools.

Consider the forthcoming book by Mike Pressler, the good-guy coach who was forced to resign in the wake of the scandal. To their credit, Pressler and co-author Don Yaeger don’t try to sugarcoat what Pressler’s players did on March 13, 2006. And it doesn’t make for easy reading, either.

Our story begins in the afternoon, when somebody proposed that the lacrosse players go to a local strip club. But several underage team members had been “carded” and denied entry to the club. So they decided to bring the strip club to them. “Every guy that we know in every fraternity and on every sports team had had strippers to their house,” one player explained. “We thought, what’s the downside?”

So team captain Dan Flannery got on the phone, using the name Dan Flannigan, and hired two strippers. But when they appeared, they were not as young or attractive as the players had hoped. Even more, one of them was so intoxicated that she could barely dance.

Now it gets really ugly. After the intoxicated dancer collapsed, the two women simulated a sex act on the floor. But that wasn’t to the players’ liking, either, and one of them asked if the dancers had brought any “sex toys.” They replied with a joke about the size of the player’s genitals. Then another student grabbed a brown broom handle and said, “Well, how about this?”

Visibly shaken, the dancers retreated to the bathroom and locked the door. Here’s where Mike Nifong said three men raped one of them.

But that’s not what happened. Instead, students slipped bills underneath the locked door to encourage the dancers to come out; the dancers emerged, and announced they were leaving; then they quarreled loudly with the students, who demanded a refund.

And as the women drove away, one white student yelled at a black dancer, “Tell your grandfather I said thanks for my cotton shirt.”

So let’s do a little experiment here. If you have a son, raise your hand if you’d like him to act like these students did. And if you have a daughter, ask yourself if you’d like her to date them.

No hands up? I didn’t think so.

That’s because the Duke lacrosse players were exhibiting the very worst of aspects of American male conduct: crude, sexist, violent, and—in at least one instance—racist. As we now know, they didn’t attack the dancer who accused them. But their words and deeds help fuel a culture where attacks of this sort are routine, expected, and acceptable.

And they’re even more acceptable in fraternities and sports-teams, the epicenters of college bad-boy behavior. As a slew of social-science research has demonstrated, fraternity members and varsity athletes are more likely than other students to engage in violence against women and also to agree with “rape-supportive statements,” such as “about half of women who report rapes to the police are lying.”

In this case, ironically, the woman who charged rape [ITAL]was[ITAL] lying. But that doesn’t make the general statement true. Some drivers are falsely accused of speeding, after all, but no one suggests that half of the tickets issued on our highways are invalid.

So why do so many of us [ITAL]think[ITAL] it’s true? Why do we ignore, downplay, or deny violence against women? The answer is complicated, but it must start with the boorish, misogynist conduct that young men learn in school.

Let’s be clear: none of the Duke lacrosse players deserved to have their names and reputations dragged through the mud by a zealous, deceitful prosecutor. But they should be ashamed, anyway. And so should the rest of us, for teaching them all the wrong lessons about the right way to behave.