While most students at Columbia University will spend the first day of classes carrying backpacks and books, Emma Sulkowicz will start her semester on Tuesday with a far heavier burden. The senior plans on carrying an extra-long, twin-size mattress across the quad and through each New York City building – to every class, every day – until the man she says raped her moves off campus.

“I was raped in my own bed,” Sulkowicz told me the other day, as she was gearing up to head back to school in this, the year American colleges are finally, supposedly, ready to do something about sexual assault. “I could have taken my pillow, but I want people to see how it weighs down a person to be ignored by the school administration and harassed by police.”

Sulkowicz is one of three women who made complaints to Columbia against the same fellow senior, who was found “not responsible” in all three cases. She also filed a police report, but Sulkowicz was treated abysmally – by the cops, and by a Columbia disciplinary panel so uneducated about the scourge of campus violence that one panelist asked how it was possible to be anally raped without lubrication.

Apparently even an Ivy League school still doesn’t understand the old adage of “no means no”.

So Sulkowicz joined a federal complaint in April over Columbia’s mishandling of sexual misconduct cases, and she will will hoist that mattress on her shoulders as part savvy activism, part performance art. “The administration can end the piece, by expelling him,” she says, “or he can, by leaving campus.”

Her performance may be singular, but the deep frustration voiced by Sulkowicz is being echoed by survivors across the United States. Despite increased efforts to curb campus assault and hold schools accountable – the FBI has changed its once-archaic definition of rape, a new White House task force wants answers, and schools like Harvard and Dartmouth have promised new policies – the nation’s university administrators are still failing young people in their care. In the last year alone, 67 schools have had students file federal complaints accusing their own colleges of violating the Clery Act or Title IX.

With the start of school underway, however, the biggest paradigm shift on rape and sexual consent in decades may just now be emerging in California, where “yes means yes” – a model for reform that feminists like me have been pushing for years – could soon become law.

Late last week, the first state bill to require colleges to adopt an “affirmative consent” model in their sexual assault policies passed the California senate unanimously. The legislation, which is headed to Governor Jerry Brown’s desk for approval by the end of this month (his office declined to comment), effectively requires the presence of a “yes” rather than the absence of a “no” – or else withholds funding from the nation’s largest state school system.

Verbal consent is best: easier to avoid the 'he said, she said' college administrators try to make rape cases out to be Sofie Karasek, senior, UC-Berkeley

The legislation additionally clarifies that affirmative consent means both parties must be awake, conscious and not incapacitated from alcohol or drugs – and that past sexual encounters or a romantic relationship doesn’t imply consent. The California bill also, importantly, specifies that “lack of protest or resistance does not mean consent, nor does silence mean consent”.

It seems like a no-brainer to only have sex with conscious and enthusiastic partners, but detractors say the standard “micromanages” sexuality. The truth is that a “yes means yes” policy “helps to create a shared responsibility, instead of the responsibility falling on women to say ‘no’,” says Tracey Vitchers, chair of the board at Safer (Students Active for Ending Rape). Anti-violence activists are clearly excited about the bill, which – if all goes well – could be adopted by more states with large public university systems.

Sofie Karasek, a senior at the University of California at Berkeley and co-founder of End Rape on Campus, also supports the new bill. Like Sulkowicz at Columbia, Karasek filed a federal complaint after she said Berkeley didn’t take sufficient action after she reported a sexual assault. As her first week back on campus was winding down on Friday, Karasek told me she thinks the California model has “created an important conversation about consent in the media and public, and I think with affirmative consent, more students will be talking about it as well.”

Indeed, a lot of students – male students, included – already are. Gray Williams, a senior at University of North Carolina at Greensboro, says he likes the “yes means yes” standard. “It’s not that big of a deal, and I appreciate having an unambiguous ‘yes’ or ‘no’ instead of having to read her body language,” he told me. Roo George-Warren, a recent graduate of Vanderbilt University, thinks some young men might be skeptical, but he insists part of the problem is that the “discourse around consent in day-to-day conversation is so unsophisticated.”

And this is what makes the legislation so important for colleges: mandating “yes means yes” in sexual assault policy puts the onus on colleges to give comprehensive consent education. If students are to abide by that standard, they need to know what it means.

So California could lead the way in redefining how we think about sexual consent. But as promising as this overdue measure may be, state legislatures and university administrators alike need to make sure they’re being as thorough as possible in this moment when real reform, for once, doesn’t seem impossible. The legislation doesn’t clearly specify whether affirmative consent means verbal or nonverbal communication. Do students need to say “yes”? Or is clear body language sufficient?

Should Gov Brown sign “yes means yes” into law, I agree with Slate writer Amanda Hess, who believes the standard going forward should itself be more sophisticated and include nonverbal cues – not just because they present a more realistic vision of how we experience sex, but because we need to talk about body language that can mean “no” as well:

If we can admit that enthusiastic consent is often communicated in body language or knowing looks, then we must also accept that the lack of consent doesn’t always manifest itself in a shouted ‘no’ or ‘stop,’ either. It shouldn’t be the sole responsibility of the uninterested party to speak up during a sexual encounter.

At Berkeley, Karasek said she remained worried that such ambiguity could be used to further hurt survivors and that requiring verbal consent would make it easier to “avoid the ‘he said, she said’ that college administrators try to make rape cases out to be.”

Facebook Twitter Pinterest An estimated one in five women is sexually assaulted during college. Emma Sulkowicz says she was raped in her own bed. Photograph: Kristina Budelis for Guardian US Opinion

We’ve come a long way in the last four decades on sexual assault, but this necessary shift to “yes means yes” will not be an easy one. (Let’s also not forget that it was just four years ago when male students from Yale University were caught on tape chanting “No means yes, yes means anal.”)

The feminist movement of the 70s shined a light on “date rape” – the most common kind of sexual assault that once went ignored is now widely-understood to be a pervasive problem. Twenty-one years ago, marital rape was still legal in some states, but now legislation decries the idea that marriage equals constant consent. Today, politicians and activists alike increasingly recognize that everything we did before is simply not enough: despite these shifts in policy and public perception, rape is still far too common – approximately one out of every five women is sexually assaulted in college.

And that’s just what’s reported, according to the White House. That’s just in America. That’s just in college.

When I spoke to Sulkowicz about her unofficial senior project – she calls it Mattress Performance: Carry That Weight – the brave 21-year-old said something I think most people who care about the issue of violence against women can relate to. “It’s going to be an endurance piece,” she said. In some ways, battling rape always has been.