Young women are often the targets of aggression when they're out in bars, but the problem isn't that guys are too drunk to know better.

Instead, men are preying on women who have had too much to drink.

When researchers at the University of Toronto and the University of Washington observed young people's behavior in bars, they found that the man's aggressiveness didn't match his level of intoxication. There was no relationship.

Instead, men targeted women who were intoxicated.

The researchers hired and trained 140 young adults to go into bars in the Toronto area and note every incident of aggression they saw. They found that 25 percent of all incidents involved sexual aggression. And 90 percent of the victims of sexual aggression were women being harassed by men.

Almost all of the aggression was physical, with about two-thirds of the aggressors physically touching women without consent. About 17 percent threatened contact. And 9 percent verbally harassed their targets.

Men may perceive intoxicated women either as more amenable to advances or as easier targets who are less able to rebuff them because they don't have their wits about them, the researchers say.

"There's no reason that women should be touched against their will," says Kate Graham, the study's lead researcher and a senior scientist at the Centre for Addiction and Mental Health at the University of Toronto. Women wouldn't accept that kind of behavior at school or on the street, she notes, but it seems to get a pass in bars, she tells Shots.

The study was published online Monday in Alcoholism: Clinical & Experimental Research.

The researchers also wanted to look into whether unwanted sexual advances were intentional or just a matter of misperception. This study points to the former, Graham says.

"If you walk through a bar and grab a woman's breasts and then disappear into the crowd, that's probably not a misunderstanding," she says. "You don't actually think that she wants you to do that."

The fact that men were more likely to take advantage of intoxicated women shows that most of these incidents aren't well-intentioned, Graham says.

And the bar staff rarely stepped in to stop the sexual aggression. "There should be training for staff on how to intervene," Graham says. "If [a bar] wants to have female patrons, they ought to make it more female friendly."

Efforts have been launched in Washington, D.C., and around the country to do just that. They provide bar staff with free training on how to respond when they see sexual harassment.

The observers rated people's level of intoxication based on the number of drinks they consumed and their behavior. Observers worked in pairs with one man and one woman to reduce potential bias.

Since the observations were made in public places in or around bars, the study doesn't tell us much about sexual assault or rape that might occur out of public view or after women leave a bar.

But the takeaway, Graham says, is that "people should stop believing that [Robin Thicke] song. The lines really aren't that blurred."

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