Our strategy for dealing with rape on college campuses has failed abysmally. Female students are raped in appalling numbers, and their rapists almost invariably go free. Forced by the federal government, colleges have now gotten into the business of conducting rape trials, but they are not competent to handle this job. They are simultaneously failing to punish rapists adequately and branding students sexual assailants when no sexual assault occurred.

We have to transform our approach to campus rape to get at the root problems, which the new college processes ignore and arguably even exacerbate. How many rapes occur on our campuses is disputed. The best, most carefully controlled study was conducted for the Department of Justice in 2007; it found that about one in 10 undergraduate women had been raped at college.

But because of low arrest and conviction rates, lack of confidentiality, and fear they won’t be believed, only a minuscule percentage of college women who are raped — perhaps only 5 percent or less — report the assault to the police. Research suggests that more than 90 percent of campus rapes are committed by a relatively small percentage of college men — possibly as few as 4 percent—who rape repeatedly, averaging six victims each. Yet these serial rapists overwhelmingly remain at large, escaping serious punishment. Neither strategy would get to the true problems: rapists going unpunished, the heady mixture of sex and alcohol on college campuses, and the ways in which colleges are expanding the concept of sexual assault to change its basic meaning.

Consider the illogical message many schools are sending their students about drinking and having sex: that intercourse with someone “under the influence” of alcohol is always rape. Typical is this warning on a joint Hampshire, Mount Holyoke and Smith website: “Agreement given while under the influence of alcohol or other drugs is not considered consent”; “if you have not consented to sexual intercourse, it is rape.”

Now consider that one large survey showed that around 40 percent of undergraduates, both men and women, had sex while under the influence of alcohol. Are all these students rape victims? And what if both parties were under the influence? Asked this question, a Duke University dean answered, “Assuming it is a male and female, it is the responsibility in the case of the male to gain consent.” This answer shows more ideology than logic. In fact, sex with someone under the influence is not automatically rape. That misleading statement misrepresents both the law and universities’ official policies. The general rule is that sex with someone incapacitated by alcohol or other drugs is rape. There is—or at least used to be—a big difference. Incapacitation typically means you no longer know what’s happening around you or can’t manage basic physical activity like walking or standing.

But if schools are genuinely interested in preventing sexual assault, they need to overhaul how they think about assault and what they do about it. Prevention, rather than adjudication, should be a college’s priority.

That means, first of all, we need to stop being so foolish about alcohol on campus. A vast majority of college women’s rape claims involve alcohol. Not long ago, 18-year-olds in many states could drink legally. College-sponsored events could openly involve a keg, with security officers on hand to ensure that things didn’t get out of hand. Since 1984, when the federal government compelled states to adopt a drinking age of 21, college alcohol policies have been a mockery. Prohibition has driven alcohol into private spaces and house parties, with schools largely turning a blind eye. When those spaces and parties are male-dominated, it’s a recipe for sexual predation. Such predation has been documented: Attending fraternity parties makes women measurably more likely to be sexually assaulted.

If colleges are serious about reducing rapes, they need to break the links among alcohol, all-male clubs and campus party life. Ideally, we should lower the drinking age so that staff or security personnel could be present at parties.

In any event, schools need to forcibly channel the alcohol party scene out of all-male clubs and teach students “bystander” prevention—how to intervene when one person appears to be taking sexual advantage of another’s extreme intoxication. At the same time, students need to be told clearly that if they are voluntarily under the influence (but not incapacitated), they remain responsible for their sexual choices.