For minor offenses, the fine in the mail is already in force.  Parking tickets, moving violations, failure to conform to ordinances related to home and yard upkeep, etc.  The confrontation was over drugs, apparently.  Drugs are illegal because we want to control the behavior of others even though that behavior has little impact on us.  Perhaps, drugs should not be illegal except relating to sale to children.  There are many ways to reduce police violence, but modern American still adheres to the notion that conformance must be backed in every respect with the threat of deadly force.