California is about to become the first place in the United States to put tough legal restrictions on the ways farmers can give antibiotics to livestock, going far beyond what new federal rules allow.

The controls come courtesy of a law that has been sent to Gov. Jerry Brown, which he will sign by Sunday. Bill 27 (prosaically titled, “Livestock: use of antimicrobial drugs”) represents the only legislation ever enacted in the U.S. that puts enforceable limits on antibiotic use, gives a state agency oversight of how farmers use the drugs, and prescribes fines if they go beyond what is allowed. (Update: Brown signed the bill one day after this was published, Saturday, Oct. 10.)

That’s a big advance. True, a number of cities (Seattle, Cleveland and Pittsburgh, among