Jerry Brown California
The so-called "yes means yes" law was signed by California governor Jerry BrownGetty

California governor Jerry Brown on Sunday signed a law requiring all state-funded colleges to implement a policy of clear, affirmative consent by students engaged in sexual activity, in an effort to curb sexual assault on campuses.

The so-called "yes means yes" law is the first of its kind in the United States to make consent language fundamental to college sexual assault policies. Advocates say the legislation will change the perception of rape.

The law defines consent as "an affirmative, conscious and voluntary agreement to engage in sexual activity" and states that silence and a lack of resistance do not signify consent. It highlights that alcohol or drugs do not excuse unwanted sexual activity.

Democratic California State Senate member Kevin de León said the legislation will kick-start a paradigm shift in how college campuses in the state prevent and investigate sexual assaults.

Instead of using the refrain "no means no", the new law requires a positive consent.

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

In January, President Barack Obama launched an initiative to combat sexual assault, as US universities are under pressure to change how they handle rape allegations. The White House declared sex crimes to be an "epidemic" on campuses - with estimates stating that one in five women are sexually assaulted while at university.

Advocates for the legislation say it will provide consistency across campuses and challenge the notion that victims must have resisted assault to have valid complaints.

The bill requires training for faculties reviewing allegations, so that victims are not asked inappropriate questions when filing complaints. It also requires access to counselling and health care services.

Yet critics say the new bill is overreaching and dangerously expands the definition of assault.

The National Coalition For Men condemned the bill as "misandric" (man-hating) saying it "gives license to false accusations, denies the accused due process, will cost the state hundreds of millions of dollars in law suits and sets the stage for ruining innocent lives."

Gordon Finley, an adviser to the coalition, wrote an editorial asking Brown not to sign the legislation, arguing it was a "campus rape crusade bill".