Endeavoring to Do Better


1980s National Spotlight

One in Four

Mary Koss and the persistent percentage

Mary Koss bumped into her life’s work on her first day in Ohio. She’d been teaching at St. Olaf and in 1975 moved to the psychology department at Kent State into focus on research. She was walking through a door as a man passed her on his way out. When he saw her he stopped, and without even a hello, he said he wanted her to sign his grant application. He’d just been turned down “because he was a man,” he explained, but with her attached, he thought he could get it funded.The guy was planning to study what happened when he showed male undergraduates pictures of female students wearing padded bras of different sizes. The men would be asked how “rapeable” each woman was, how likely they would be to have sex with the men, and if each woman were raped, how much it would be her fault. Koss turned him down flat, but she was intrigued by the subject. Her first major study, conducted in 1978, investigated the question “How prevalent is rape on campus?”At the time, surveys about sexual violence asked simply, “Have you ever been raped?” Koss wondered if the numbers would change if the language did. Borrowing a technique from research on alcoholism, she omitted the word “rape” and asked instead “Has someone ever used force or threatened harm to get you to have sex with them?” Using this lens, the numbers rose. One in four female respondents said they had experienced rape or attempted rape at college. They hadn’t been assaulted by strangers who pounced on them in a dark alley, they had been forced into sex by people they knew—boyfriends, friends, and acquaintances. Koss called this phenomenon “hidden rape” and “acquaintance rape.” She found in a later study that 84 percent of rape victims had known their attacker.  Koss expanded her scope in 1987, when she was commissioned by the National Institute of Mental Health to survey more than 6,000 students from 32 colleges and universities. It was the first national study of rape on campus, and her results were the same: one in four female subjects had experienced rape or attempted rape at school. Mirroring the way victims of assault are frequently doubted and second-guessed, national media covered Koss’s study with outrage and scorn. They adopted the more sensationalistic term “date rape” and impugned Koss’s integrity along with her results, even accusing her of changing survivors’ accounts to beef up her data. But Koss’s numbers were solid. In 2020 the American Association of Universities analyzed surveys returned by more than 181,000 students from 33 schools and found that the proportion of students willing to reveal that they’d experienced sexual assault (nonconsensual sexual contact by physical force or inability to consent) on campus was 26 percent of women, 23 percent of transgender and nonbinary students, and nearly 7 percent of men. Less than half (45 percent) of victims said it was very or extremely likely school officials would take a report of sexual assault seriously. The majority of them didn’t report their assaults. Sexual violence continues to be as big a problem now as it was when Koss did her first study in 1978.