I am an office assistant at a law office in San Francisco on an hourly pay. I do not get paid for 30 min lunch, but my co-workers who are also office assistants do get paid for a 30 min lunch. They were working for that office before I came. Should I be paid for lunch also? Should the lunch break policy be the same for everyone who is paid hourly? What does the law say?

thanks

The law does not require that any breaks in excess of 20 minutes be paid.

It sounds like your employer changed their policy regarding paying for lunch breaks before you joined the firm. They are not violating any laws by "grandfathering" the more senior employees and continuing to pay for their lunch break and not paying for yours.