The measure was pushed by Los Angeles County, which ran afoul of state law in 2011 when supervisors held a closed-door meeting with Brown to discuss his plan to reduce prison crowding by keeping low-level offenders in county jails rather than sending them to state lockups.
The new law adds the governor to the list of people with whom local lawmakers can meet confidentially to discuss "matters posing a threat to the security of public buildings, services and facilities and public access to public services or facilities."
Also on Monday, lawmakers revised a budget bill to eliminate a proposal that could have hampered public access to local government records in California. Brown requested the provision earlier this year but backed away from it last week after a public outcry.
