My wife got a letter over the weekend from the State Patrol. According to them they linked via the driver license database and vehicle registration database and found that she is a part owner of a motorcycle and does not have the proper endorsement to operate it.
Clearly they were hoping she would get her motorcycle license band pay the required fee to do so.
So to cross-check the driver license database with the voter file to protect the integrity of the voter registration list is too hard, but to cross-check it against the vehicle registration list to get more money is a priority.