On Sunday, Gov. Jerry Brown signed a “yes means yes” law, making California the first state in the nation “to require all state colleges to adopt a policy of unambiguous, affirmative consent by students engaged in sexual activity.”

Al Jazeera America reported, “The legislation defines consent as ‘an affirmative, conscious and voluntary agreement to engage in sexual activity.’ It also states that silence and a lack of resistance do not signify consent and that drugs or alcohol do not excuse unwanted sexual activity.”

This landmark law is part of a nationwide effort to curb sexual assault on U.S. campuses.

Nearly 1 in 5 college women is sexually assaulted by the time she graduates, with just 12 percent of them reporting the assaults, according to The White House Council on Women and Girls reported. The Department of Justice says this is a much lower rate than the estimated 40 percent of assaults that are reported by the general population.