The box allows the authorities to confirm your identity and your enrollment to the database when your card is in their hand. They call the hotline, give them your number and they confirm your identity. Not saying there are no crooked politics happening here though, very well could be. But the database does not openly provide authorities with information, it is used to confirm your status within the law i.e. number of plants, patients, caregivers, card expiration, usable material etc.
Schuette wants to change all of that and hand it to the cops though! We need to stop him from slaughtering our rights.