San Francisco’s groundbreaking policy protecting sex workers is now being pitched on the state level.

California Sen. Scott Wiener, D-San Francisco, will introduce legislation Monday that would prevent law enforcement from arresting and charging sex workers who come forward as victims or witnesses to serious crimes. The proposed law, SB233, would also prevent officers from using condoms as probable cause to arrest a sex worker in any situation.

“Right now, we know there are sex workers who are victimized or witness crimes and are scared to come forward because they think they are going to be arrested,” Wiener said. “We want to create every incentive for sex workers to feel safe in reporting crimes.”

The former city supervisor will announce the legislation at a press conference Monday at St. James Infirmary, a peer-based health and safety clinic for sex workers in San Francisco’s Tenderloin. The law would mirror the city’s landmark policies that went into effect last year that seek to prioritize more serious crimes and protect human trafficking victims.

Police Chief Bill Scott barred officers from arresting sex workers when they are victims or witnesses to sexual assaults, human trafficking, robbery, assault, kidnapping, and other violent crimes. District Attorney George Gascón similarly said his office will not prosecute sex workers for prostitution when they come forward as victims or witnesses to crime.

Wiener said it was important to add a component of his legislation to stop police from arresting sex workers simply for carrying condoms — a practice San Francisco abandoned long ago.

“There are police departments that will arrest and charge sex workers based on having, say, five condoms,” he said. “The last thing we should be doing is signaling to sex workers that if you carry condoms to avoid HIV, that’s going to get you arrested and prosecuted.”

The proposed state law was welcomed by sex worker and human trafficking advocates.

Carol Leigh, director of the Bay Area Sex Worker Advocacy Network and a vocal advocate for the decriminalization and legalization of sex work, called the legislation “a step in the right direction.”

During her time as a sex worker in the early 1980s, Leigh said, she was raped but didn’t come forward to report the crime out of fear she would be targeted for arrest.

“The person that raped me went on to rape other women,” Leigh said. “I think there are a lot of ways this legislation and these policies can positively impact sex workers.”

It’s unclear whether the bill will make it through the notoriously tough legislative process. Even popular bills die in committee, and Wiener expects to see opposition to SB233 from conservative groups.

He hopes Democratic supermajorities in both houses will help.

“It’s going to take a lot of work,” Wiener said. “We’ll have to make the case that this is good policy that will improve public safety and public health.”

Evan Sernoffsky is a San Francisco Chronicle staff writer. Email: esernoffsky@sfchronicle.com Twitter: @EvanSernoffsky