The databases in question hold information such as driver licenses, car registration, criminal histories,warrants, missing persons, etc. In Ohio the main law enforcement database is LEADS which also ties into national criminal justice databases, Access to LEADS is regularly AUDITED. People who misuse it are routinely prosecuted. These databases are very important to public safety. You can never prevent misuse, but you can hold users accountable for their use of the system.
Maryland has METERS, which ties into NCIC, and is similarly audited. People are punished for misuse of METERS, sure. But that isn't the only database. Counties and municipalities have their own records and document management systems, which have confidential information in them, often in greater detail than METERS- full police reports without redaction, calls for service, and so on. Implementing auditing at this level is a hard sell with the shrink in state/local funding and manpower. And let's be real, having strict audits of these databases is just not going to be a high priority for a lot of agencies. So I guarantee you that, if you look around, there are many agencies that have no auditing in place for their internal databases that hold confidential information. Hence the potential for abuse. I'm not surprised that this is such a widespread problem, not at all, despite strict controls that exist for the state databases that tap into the national criminal database.