SACRAMENTO, Calif. (AP) — A year after San Francisco's transit agency touched off a global free speech debate by jamming cellphones to block a protest, lawmakers are taking steps to pre-empt a similar scandal.

On Thursday, the state Assembly approved a bill that would prohibit agencies from disrupting cellphone service without probable cause and a court order.

"Open and available communication networks are critical to public safety and a key element of a free and open society," Sen. Alex Padilla, who wrote the bill, said in a statement.

The Los Angeles Democrat cited 911 access as a key concern.

Officials with the Bay Area Rapid Transit system came under fire last year when the agency cut subterranean cellphone and wireless data service in San Francisco subway stations to disrupt a planned protest. The move sparked even larger protests and had critics around the country comparing the agency to a Middle Eastern dictatorship.

Assembly members condemned the BART decision on Thursday and expressed hope the SB 1160 would serve as a wakeup call to other agencies considering jamming cellphones.

"The dysfunction of the BART system is well known in my area," said Assemblyman Tom Ammiano, D-San Francisco.

Ammiano called last year's cellphone jamming "undemocratic" and said the agency has a history of "reacting inappropriately by even the most mild and benign civil actions by the populace."

BART did not immediately respond to requests for comment. Following last year's incident, the agency adopted a policy that permits cellphone jamming without court review if officials believe a service disruptions or illegal action is imminent.

After some revisions in the Assembly, the bill now goes back to the Senate for final approval.