California Atty. Gen. Jerry Brown on Tuesday waded into the controversy over a new law that aims to reduce the state prison population by saying it applies to county jail inmates but should not be read as requiring immediate, large-scale reductions of their jail populations.

The bulletin to law enforcement agencies around the state came as the union representing Orange County Sheriff's deputies became the second major policing organization to go to court to block use of the law, which appears to speed the process under which county jail inmates can be released by changing the formula used to determine time off for good behavior.

Brown's spokeswoman Christine Gasparac said it was the job of the attorney general to enforce the law. But at the same time, she said, Brown wanted to reduce confusion about how counties should interpret the law. Brown believes that the formula under which inmates earned credit for good behavior should be calculated beginning when the law went into effect -- Jan. 25 -- rather than when an inmate began serving time.

"We filed briefs in the courts that argue this position," Gasparac said. "We want all the counties to know that's how we interpret the law and we hope it will give some guidance."

The clarification appears to have come too late for some.

More than 300 inmates have been released in Orange County in the last few weeks and about 200 in Sacramento County, including a man who allegedly assaulted a woman hours after being released early.

Sacramento, Orange, Riverside, San Bernardino, Ventura and other counties have said their legal counsels advised them that the law applied retroactively to county jails, so they created release plans when the law took effect last month. In all, more than 1,500 inmates have been released.

The legislation, signed by Gov. Arnold Schwarzenegger last year, was designed to reduce the state prison population in the wake of the state's financial crisis and court rulings on prison overcrowding. Officials have said the law would reduce the state prison population by 6,500 "low-level" offenders over the next year, including inmates incarcerated for nonviolent crimes such as theft and drug possession.

Like many law enforcement officials across the state, the union representing the Orange County Sheriff's deputies said they were surprised and disappointed by local authorities' decision to interpret the release as applying to a broad population of their inmates.

"[The] early release program endangers our county and the people who live and work here," Wayne Quint, president of the Assn. of Orange County Deputy Sheriffs, said in a statement. "We can't be releasing drug dealers, car thieves, drunk drivers, spousal abusers and other offenders back into our community early before they serve their sentences. In some instances, we are already seeing some of these individuals immediately turn around and commit new crimes."

The O.C. sheriff's union's decision to go to court comes a week after a Sacramento County judge ordered a temporary halt to that county's early releases, saying the legislation applies only to state prisons and not to county jails. The judge sided with the local sheriff's deputies union, which filed suit against the Sacramento County Sheriff's Department to block the releases.

In contrast, the Los Angeles County Sheriff's Department has not released any inmates early because of the law. L.A. County requires that most male inmates serve 80% of their sentence, and officials said they won't reduce that requirement because of the new law because they don't believe it applied to local counties.