(Mike Blake/Reuters)
Irina D. Manta is a professor at the Maurice A. Deane School of Law at Hofstra University, its associate dean for research and faculty development, and the founding director of its Center for Intellectual Property Law.

Anyone who uses an online dating site — Tinder, Bumble and the rest — quickly learns that people don’t always look like their photos, they sometimes add an inch or two to their height and maybe they fudge their weight. One study found that 80 percent of people lie in their profiles. Many falsehoods are mild, easy to see through within seconds of meeting someone in person and do little harm.

But other lies are more dangerous: They become instruments of sexual fraud. A 44-year-old woman in Britain, for example, fell in love with a man who told her he was a single businessman who often traveled for work. A year later, she learned that he was a married London lawyer using a fake name to sleep with several other women whom he had apparently tricked in the same way.

There have always been people who tell lies to get sex, but apps make it easy to deceive victims on an unprecedented scale, and in relative anonymity, well outside the perpetrators’ social circles. Yet we punish low-level shoplifting, or false claims in commercial advertising, more harshly than we punish most forms of sexual deception, despite the suffering and harm to one’s dignity the latter brings. For a woman in her late 30s or early 40s who wants to marry and have children, the opportunity cost of a fraudulent relationship can add another dimension to the pain in the form of diminished fertility.

Legislators have been wary of wading into this terrain, for reasons both reasonable (it can be difficult to document deception or measure the harm it causes) and less so (nonmarital sex is a risky business, and people who are duped supposedly deserve what they get). In a forthcoming law review, I propose that state lawmakers confront this issue with statutes that would punish, with relatively modest sanctions, material lies that deceived someone into having sexual relations. Confining the cases to small-claims court — which, in the District, would mean that fines would be capped at $10,000 — would deter individual liars, and the cost would add up fast for serial fraudsters.

One way to measure dating-app fraud would be to look for information that (1) was misleading and (2) involved one or more material facts about a person that (3) a reasonable person could have used to decide whether to engage in sexual intercourse. While such legal intervention wouldn’t capture every possible form of sexual fraud (think of lies that originated in a bar rather than on an app), these measures would make a real dent in addressing some of the large-scale problems in today’s dating marketplace.

This legal standard is modeled on how we treat misleading commercial branding through statutes like the Lanham Act. In both the world of brands and the world of dating, there’s an incentive for sellers to misrepresent what they are peddling to gain an advantage. Yet the law recognizes that outright deception about important facts that shape the decision to buy a product not only inflicts real harm on individuals, it also causes markets to break down, because “search costs” balloon. If people can’t trust sellers, they will be forced to undertake expensive or time-consuming investigations of products, or they will simply hold on to their money.

Such concerns led the U.S. Court of Appeals for the Federal Circuit, in an important 1988 case , to reject trademark registration for the name “Lovee Lamb” for synthetic car-seat covers: The products were not made with real lamb’s wool, and a mistaken impression that they were might have swayed purchasing decisions. We can use a similar standard to deal with wolves in sheep’s clothing in the dating arena.

Currently, the law only haphazardly penalizes misrepresentations in the context of sex. Some states make it illegal for people to lie about their sexually-transmitted-disease status (such as HIV positivity), although prosecutions are rare. In other situations, the legal landscape shields victims from some harms and not others without much rhyme or reason, largely driven by historical happenstance or high-profile stories of abuse that drove narrow legislation.

One case that resulted in legal punishment involved a Tennessee defendant who telephoned women and duped them into believing that he was a current sexual partner or friend. He then asked to have sex with the women after they’d blindfolded themselves, supposedly to fulfill a fantasy — and either entirely or partly succeeded in the ruse with three victims. He was convicted of two counts of rape by fraud and one count of attempted rape by fraud, which resulted in a 15-year sentence. In 2002, a California man broke into a sleeping woman’s bedroom and let her believe that he was her husband (who was asleep next to her), then penetrated her. The perpetrator was convicted of rape and sexual penetration by artifice, pretense or concealment, and assault with intent to commit rape, which resulted in a sentence of six years in state prison.

The impact of dating apps, and the associated lying, is only going to grow. By 2013, one-third of married Americans had met their spouses online, and it is estimated that by 2040, more than two-thirds of people will have met their significant others that way. (I found my own husband on Bumble. ) But even as apps amplify the harms caused by lies, they make documenting lies easier, because people’s misleading profiles can be reviewed, and text messages repeating the lies can be saved.

Perhaps all seduction involves embellishment — after all, isn’t makeup or a push-up bra trickery, when the truth might be disappointing? But lies exist on a spectrum, as the law around false advertising already recognizes. You are allowed to boast that a product is “the best in the world,” whether or not that is accurate in the eye of the buyer, and dating-profile claims of being “witty” or “the most amazing cook you’ll ever meet” should be treated similarly. New laws in the dating area should focus on lies that are clearly false, are not easily discoverable before sex takes place, and have a potentially large dignitary or emotional impact. Lies related to physical appearance would thus typically not be punishable, while ones about marital status, fertility circumstances (say, existing children or the ability to have future children) or employment may lead to sanctions.

States might draw the line on deception differently. A number of them may decide that a married man who omits his status from his profile is guilty of misrepresentation. A more cautious approach that requires explicit misrepresentation could also be justified.

Some Tinder users who bend the truth might say they do it so that potential mates don’t weed them out. They hope to win people over in person, and at times they succeed. But “I won’t be able to get laid as easily” is a poor argument for lying in the sexual setting. That line of thinking reflects an often misogynistic attitude of entitlement to sex that, in its more extreme forms, has been used to justify rape and has been embraced recently by the “involuntary celibacy,” or incel, movement.

Most people understand that there is no right to have sex with a particular person — or with anyone at all, if nobody is willing. The #MeToo movement rightly subjects all sorts of behaviors in the dating arena to greater questioning, and the legal boundaries in this context are up for fresh discussion. How to handle sexual fraud in the age of Tinder should be a part of those debates.

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