Some of those plants came from Rosenthal's grow room in Oakland. Oakland's city government had officialized its relationship with Rosenthal and his medical grow room so he could be immunized from prosecution using the same protections that allow an undercover police officer to break the law while doing his job and not be prosecuted for it. The city was attempting to comply with California's 1996 medical marijuana law, which stipulates that government ensure a safe supply of marijuana to patients.games