California colleges welcomed Monday a new law requiring so-called affirmative consent for partners having sex on campus -- dubbed a "Yes means Yes" law -- in what is thought to be a first.
Under the law, signed late Sunday by Governor Jerry Brown, partners will have to give "affirmative, conscious, and voluntary agreement to engage in sexual activity" before they do so.
Affirmative consent cannot be given by someone who is asleep, unconscious, or if he or she is "incapacitated due to the influence of drugs, alcohol, or medication," said the text of Bill 967, about sexual assaults on campus.
The University of California (UC) welcomed the new law, sponsored by state Senator Kevin de Leon.
"We have worked with and supported Senator De Leon on SB 967 and are pleased to see the bill become law in California," UC spokeswoman Dianne Klein told AFP.
"The affirmative consent definition is one of many factors that is assessed when sexual violence is investigated and adjudicated on our campuses. But it is an extremely important one," she added.
Students also welcomed the new law, while voicing a note of caution.
"UCSA commends Governor Brown for signing SB 967," said Jefferson Kuoch-Seng, spokesman for the University of California Student Association (UCSA).
"The signing of this bill marks a crucial step towards the direction in which universities should treat survivors of sexual violence and their offenders. SB 967 creates the first ever affirmative consent, or `yes means yes,` standard for universities," he told AFP.
"But there is still work to be done. UCSA will continue to advocate, educate, and raise awareness against sexual violence" through its own campaigning, he added.
De Leon, the bill`s sponsor, said: "The conversation on sexual assault on our college campuses turned an important corner today from chatter to action.
"Students at every California college campus will have basic protections to promote prevention, accountability and healing," he added, cited by the Los Angeles Times.
The bill was one of several signed into law by the Democrat governor on Sunday, ahead of a Monday deadline for doing so. De Leon said last week that California would be the first US state to pass such legislation.
Earlier this month, US President Barack Obama vowed to fight sexual violence on college campuses, launching a campaign to banish the "quiet tolerance" of assault.
He noted that about one in five women is sexually assaulted during her college years.
"Of those assaults, only 12 percent are reported. And of those reported assaults, only a fraction of the offenders are punished," he said.