A Washington Post-Kaiser poll found that 1 in 5 women say they were sexually assaulted while in college. One of the poll’s findings was that students differ on what constitutes consent. We asked some other local college students to define the word. (Jayne W. Orenstein and Jorge Ribas/The Washington Post)

Beer pong, body shots and keg stands. Fraternity parties, house parties and bar crawls.

College, for many students, is a generously spiked four years.

And with all that alcohol comes an increased risk of sexual violence, according to a Washington Post-Kaiser Family Foundation poll that provides new evidence of the link between intoxication and sexual assault.

Heavy drinking is one of the most significant predictors of sexual assault in college, according to the poll of 1,053 current and recent college students. Analysis of the results found that women who say they sometimes or often drink more than they should are twice as likely to be victims of completed, attempted or suspected sexual assaults as those who rarely or never drink. Several male victims also pointed to alcohol’s role in their assaults.

Stuart Dunnings III, a county prosecutor in Michigan whose purview includes 50,000-student Michigan State University in East Lansing, said many of the rape cases that come across his desk involve two young people who had been drinking.

“Alcohol is the date-rape drug,” ­Dun­nings said. “That’s what I tell people.”

East Lansing was awash in alcohol on the sun-soaked last day of final exams before graduation this spring. When a bar offering cheap pitchers of beer opened early, at 10 a.m., the line of students waiting to get in stretched down the block. Multiple house parties studded each block near the Big Ten campus; knots of students gathered on front lawns and porches, their plastic cups and beer bottles littering the neighborhood.

Though the legal drinking age is 21, students say alcohol lubricates university social life from the beginning of freshman year. It is “liquid courage” that lowers inhibitions and makes it easier to meet people, including those who might be interested in hooking up — the ubiquitous term for casual sexual encounters.

But the combination is combustible: The nation’s campuses are filled with concentrations of young people who are exploring their sexuality, inexperienced drinkers enjoying newfound freedom from their parents while gaining access to seemingly unlimited amounts of beer and liquor.

“There is this idea in our college culture that alcohol and sex should always be available,” said Kyra Stephenson, an ­anti-sexual-violence activist who graduated from Michigan State last month. “The whole context around alcohol is this is something we do to facilitate sex.”

In interviews with dozens of students who responded in the poll that they had experienced unwanted sexual contact while in college, most said they had been drinking before the incident. That’s consistent with the poll’s finding that two-thirds of survivors said they had been drinking just prior to their assaults.

Some said they had been too drunk to know or articulate what they wanted and what they didn’t want. Some said they were so intoxicated they lost awareness, later finding they had been raped while blacked out.

Others said they suspected they had been assaulted but were too intoxicated to remember the details and never found out for sure.

One student interviewed by The Post said she was 19 and a freshman at Boston University when she attended a fraternity party. She said she gravitated toward the only guy she knew. They played beer pong, and he encouraged her to drink more and more.

“He made sure I was drinking the entire time, even though I was probably already in an unsafe condition,” she said.

She got nervous when he began to touch her, but she didn’t want to make a scene: “I know it sounds so stupid, but when you’re really young and these cool frat guys invite you over, you don’t want to do anything to mess that up.”

She has only the vaguest memory of going upstairs. She awoke around sunrise the next morning, alone in a tiny room, her clothes on the floor. “I don’t know that I had sex, but I have a feeling I did,” she said.

She took a morning-after pill and got tested for sexually transmitted diseases. She didn’t report the incident, though she wishes now that she had. When she later saw the man on campus, they made eye contact, and she had a panic attack.

“I didn’t feel okay. I wasn’t fine,” she said. “To see somebody in the dining hall and freak out all over again. . . . I didn’t feel fine at all.”

Students are more likely to consider alcohol a problem on campus than sexual assault, according to the poll.

Nearly 40 percent of students said that when they drink socially, they sometimes or often drink more alcohol than they should, according to the poll. Another 3 in 10 said this happens “rarely,” and another 3 in 10 said they never drink more than they should or don’t drink at all.

Students involved in Greek life are more likely to drink heavily, according to the poll. Just more than half of fraternity and sorority members reported regularly drinking more than they should, compared with 35 percent who do not belong to fraternities or sororities.

Drugs and alcohol complicate efforts by university officials and police officers to investigate cases and come to conclusions about whether an assault occurred and whether someone was too incapacitated to consent.

When, for example, does a person cross the line from intoxicated to incapacitated? And what if both people claim to have been incapacitated? Whether a case comes before university administrators or a criminal jury, someone who was not in the room has to make those judgments.

“That is where a lot of the difficulty lies,” said Paulette Granberry Russell, a Michigan State official whose office oversees campus sexual assault investigations. “To the extent that drugs or alcohol are a factor in what we have to evaluate . . . it makes it particularly difficult to ascribe responsibility.”

Granberry Russell said adults should be free to drink as much as they want and that drunkenness should never be a justification for being victimized.

“But it can place you at greater risk of something bad happening to you,” she said. “It is not victim-blaming; it is not being a rape apologist. It is, I think, a fact.”

One woman was 18 and in her first semester at the University of North Carolina at Wilmington when she went to a party in a dorm room. She was drunk when she realized that another student had initiated sex.

“Someone just started having sex with me without my consent. I guess probably because of the alcohol,” she says now, seven years later. It ended quickly after she told him to stop, but it’s still something that bothers her.

She can’t remember how it started.

“I was really drunk, and I just kind of remember becoming aware that it was happening,” she said. “I think as far as the spectrum of things that could go wrong, I think that it’s sort of understandable. . . . It could’ve been conceived as consent in a way. It wasn’t like I said no and it happened anyway.”

But she doesn’t think she affirmatively agreed to anything.

“I feel like I should have been able to verbalize ‘I would like to do this’ or ‘I wouldn’t like to do this’ before it happened,” she said.

Nearly 8 in 10 students say drinking less would be an effective way to prevent sexual assault, according to the poll. Many survivors interviewed by The Post said their experiences caused them not only to limit their alcohol consumption but also to be more careful about where and with whom they drank.

A student at the University of South Carolina said she never has more than two drinks if she is out, and she holds onto them so she knows what she is actually drinking. It’s the same rule most women she knows follow, she
said.

She got careful after a bad night. She was attracted to a guy she met in a bar, and when he invited her back to his place to smoke marijuana, she joined him.

He just assumed that meant they would have sex, she said. She told him to stop, and she started to cry. He told her to be quiet, she said.

“You’re hurting me,” she told him. “I’m bleeding.”

But he didn’t stop.

“He got rough with me,” she said, “to the point that if I had gone to the cops and gotten the rape kit,” there would have been physical evidence that it wasn’t consensual. “But, I just knew that I was drunk when it happened. The fact that I couldn’t leave, that I had to rely on him to take me home afterward, I thought that would be used against me.”

“That’s the last time I ever went home with a guy,” she said.

She can see plenty of concerns with her own behavior, and that’s why she decided to change it. But she also says this: “If I were a guy, I never would have done this to anyone.”

While the survey found that most students think drinking less would be effective in preventing sexual assault, they are evenly split about whether cracking down on campus drinking and other violations of alcohol-related rules would make a difference.

Adam Newman, a 2014 graduate of the University of North Texas who responded to the poll, said stiffer alcohol enforcement might lead to more drinking.

Perhaps the solution is to lower the drinking age, he said, so young people learn how to drink responsibly before they get to college and getting drunk loses some of its forbidden-fruit allure.

“The appeal of ‘Ooh, parental supervision is gone, we’re going to get smashed’ is not there,” he said.

Newman said teachers and parents should recognize that young people are going to drink and should teach them how to do so responsibly.

Thinking that teens are going to wait until they are 21 to drink is like thinking that abstinence-only education is going to keep kids from having sex, he said. “It’s a fairy tale.”

Some students said they thought that they could help prevent campus sexual assaults by telling their stories, so other young people have a better sense of the ways in which assault can happen and the danger that alcohol can present.

A 20-year-old freshman at Virginia Commonwealth University said she got way too drunk at a rowdy party during the school’s 2014 summer term. The only person she knew was her roommate.

She said she was dancing with a stranger, an older student who also was drinking heavily. She collapsed on a couch and told him she felt sick.

She remembers him suggesting that she go upstairs with him and lie down for a bit. “In the back of my mind I was like, ‘Don’t go upstairs,’ ” she recalled. “But I also thought that would be safe.”

Upstairs, she threw up in the bathroom. He led her to a bed. She didn’t want the sex that followed, but she was in no shape to stop it.

She woke up the next morning, threw up again and went looking for her lost eyeglasses. As the days passed, she got angrier. A friend described the episode as an example of “rape culture” because the man apparently was okay having sex with a nearly incapacitated woman.

Culture or not, she wishes she hadn’t let herself go to that bedroom.

“I was too drunk to say no. But if I wasn’t drunk, I wouldn’t have gone upstairs at all,” she said. “Nothing that happened that night would have happened if I’d been sober.”

Nick Anderson, Scott Clement and Peyton M. Craighill contributed to this report.