“SEX game gone wrong,” “sex game gone awry,” “sex-mad flatmate,” “sex-crazed killer.”That’s from just the first three minutes of the ABC News special on Amanda Knox last week, a veritable drumbeat of sexual shaming that leaves no doubt about what elevated a college student accused of murder into an object of international fascination, titillation and scorn.

It wasn’t the crime itself. It was the supposed conspiracy of her libido, cast as proof that she was out of control, up to no good, lost, wicked, dangerous. A girl this intent on randy fun was a girl who couldn’t be trusted and got what was coming to her, even if it was prison and even if there was plenty of reason — as the eventual reversal of her initial conviction made clear — to believe that she might not belong there.

“Knox knew, it seemed, no boundaries, leaving a vibrator in a transparent washbag and enjoying one-night stands,” wrote Tobias Jones in a 2011 article in the British newspaper The Observer. One-night stands? How could she?!? Of course if a guy has one of those, it’s a triumph: all the pleasure, none of the commitment. And boys, after all, will be boys.

We’ll never know precisely what happened on the night in Perugia, Italy, in 2007 when Meredith Kercher, 21, was killed. Knox, her housemate, was found guilty, then acquitted and will soon, despite the profoundly flawed case against her, face another trial. The Italian judicial system works about as smoothly as the Italian government.

But we know this: the double standard concerning men’s versus women’s sexuality not only survives but thrives, manifest in the enduring notoriety of “Foxy Knoxy,” whose memoir was published on the same day last week that the ABC News special aired. Keep the rest of her story the same but make her a man in the midst of erotic escapades abroad. Are we still gawking? Is ABC trumpeting Diane Sawyer’s exclusive sit-down with the lascivious pilgrim?Similar questions can be asked about Jodi Arias, 32, whose murder trial in Arizona was winding down last week. The Arias case hasn’t made quite the leap from the tabloids into the mainstream that Knox’s did. But HLN, the cable network on which Nancy Grace fulminates, has enjoyed a ratings bonanza with its saturation coverage of the courtroom proceedings.

Arias has admitted to stabbing, shooting and slashing the throat of a former lover: an act of self-defense, she unpersuasively claims. And while his death was certainly grisly enough to explain a baseline of media interest, the amount of attention it has received stems from the courtroom juxtaposition of the defendant, outfitted in nerdy eyeglasses and a frumpy hairstyle, and evidence of what a steamy, pliable playmate she was. It stems from pictures of her genitalia that she let her lover take, audiotapes of the phone sex that the two of them had — and that she recorded. It stems from the shock and censure of such potent female desire.

Knox and Arias aren’t just women accused of murder. They’re minxes accused of murder, sitting in their courtroom seats with scarlet letters emblazoned on their chests, no jury needed to pronounce them guilty of wantonness at the very least. For men, lust is a tripwire. For women, it’s a noose.

I’ve heard quite a bit lately about David Petraeus’s road to redemption. I’ve heard less about Paula Broadwell’s. Yes, he’s the more public figure, but the disparity also reflects the way their affair was often portrayed in the first place. He strayed; she preyed. He was weak; she was wily. He was the fly, she the spider.

Let’s bring a few other recent news stories into this. Let’s indulge in a few hypotheticals.

WHAT if it had been Antonia Weiner who took to Twitter and there had been a different architecture to the image she tweeted? Would she be able even to entertain the idea of a political comeback? And would the spouse standing dutifully by her be seen as a brave and magnanimous stalwart, the way Huma Abedin is viewed in some quarters, or dismissed by one and all as a pitiable pushover?Had a Southern governor named Marcia Sanford been entangled with a Latin lover when reputedly hiking the Appalachian Trail, would she today be her party’s nominee for an open Congressional seat? We know the answer, and we know that Wilhelmina Clinton and Newtina Gingrich wouldn’t have rebounded from their infidelities as robustly as Bill and Newt did.

Men get passes, women get reputations, and real, lasting humiliation travels only one way. The size and scope of that mortification, despite many decades of happy talk about dawning gender equality, are suggested by recent news stories of one teenage girl in California and another in Nova Scotia who hanged themselves after tales or cellphone pictures of their sexual violation circulated among peers. It’s impossible not to wonder if shame drove them to suicide, and it’s impossible not to ask what sort of world allows the victims of such assaults to feel more irredeemably branded — more eternally damned — than their accused assailants by all appearances do.

I’ll tell you what sort: a world in which there’s a cornucopia of synonyms for whore and slut and no comparably pejorative vocabulary for promiscuous or sexually rapacious men. A world in which Knox’s vibrator and the lingerie she was said to have bought in a Perugia store were presented not just as newsworthy but as germane to the charge of murder against her: referendums on her character, glimmers of her depravity, clues to precisely how a good girl went bad. A world in which her erotic appetite made her a “man eater,” as the Italian press wrote and as the rest of the world more or less parroted. A world in which her tally, scribbled on a sheet of paper in her prison cell, of seven sexual partners in all of her life was seen as sensational. A similar count for a guy in his early 20s would provoke not derision but disagreement: swordsman or slacker?When we chart and lament the persistence of sexism in society, we look to the United States Congress, where women are still woefully underrepresented. We look to corporate boardrooms, where the glass ceiling hasn’t really shattered. But we needn’t look any further than how perversely censorious of women’s sex lives we remain, and how short the path from siren to slut and from angel to she-devil can be.