The California Department of Public Health’s (CDPH) Medical Marijuana Identification Card Program (MMICP) website says that the program

“was specifically established to create a State-authorized medical marijuana identification card (MMICP), along with a registry database for verification of qualified patients and their primary caregivers. Participation by patients and primary caregivers in this identification card program is voluntary. The MMICP Web-based registry allows law enforcement and the public to verify the validity of a qualified patient or primary caregiver’s MMICP as authorization to possess, grow, transport, and/or use medical marijuana within California.”

O’Shaughnessy’s emailed the California Medical Marijuana Identification Card Program February 26 to ask:

If joining the registry is voluntary and a medical cannabis user declines to be involved, how will law enforcement be able to “verify the validity of [said] qualified patient or primary caregiver’s… authorization to possess, grow, transport, and/or use medical marijuana within California?”

It seems like one of those riddles Oedipus had to solve. We will share the MMICP’s response.