You can post signs indicating that the premises are being video recorded. The sign must be in an obvious place with appropriate sized letters. It would be in your best interest to contact an attorney that will pull any laws for you. I would suggest the other attorneys that have responded as they seem to know the area of law.
Marijuana is against federal law. Federal law supersedes state law. A person could be charged and convicted for marijuana related crimes such as possession, cultivation, distribution, manufacturing, transportation, and conspiracy.