California Governor Jerry Brown has signed the "yes means yes" bill, which requires all state colleges to ensure students gain unambiguous, affirmative consent before engaging in sexual activity. American universities have come under fire for mishandling campus rape cases, with Columbia senior Emma Sulkowicz most recently pledging to carry her mattress with her at all times until her rapist is expelled or leaves the school.

The historic bill seeks to eradicate the idea that silence or lack of protest constitutes consent and puts in place legal guidelines for colleges to follow in the event of sexual assault. 

Under the new law, consent can still be non-verbal, so lovers do not have to read out a contract before getting busy. According to the rule, there must be "an affirmative, conscious and voluntary agreement to engage in sexual activity". That can include a nod of the head or a physical invitation to move closer.

"Every student deserves a learning environment that is safe and healthy," senator Kevin De Leon said in a statement. "The state of California will not allow schools to sweep rape cases under the rug. We've shifted the conversation regarding sexual assault to one of prevention, justice and healing."

California's bill ensures that there will now be mandatory support networks for rape victims as well as training programmes for counsellors, and demands a solid infrastructure for dealing with "rape culture" on college campuses. The law applies to any post-secondary schools that receive state money to support students.

Not everybody is happy with the bill, with one Gordon Finley of the National Coalition for Men (naturally) writing to Jerry Brown to claim that the law presumes guilt on the man's part.

But the law has been welcomed by those who say that many rape cases occur without a woman saying "no" out loud. For Californian anti-rape university groups like UCLA's 7000 in Solidarity, the new law will hopefully change attitudes towards sexual consent. 

UCLA campaigner and student Savannah Badalich told Associated Press: "This is amazing. It's going to educate an entire new generation of students on what consent is and what consent is not... that the absence of a no is not a yes."

Watch the 7000 in Solidarity make a stand against campus rape below: