It is highly doubtful that Wright was pulled over for an outstanding warrant. The police were probably just on a fishing expedition or bored and used the expired tags as a pretext to pull over someone. They run your plates and license AFTER they pull you over. When they pulled that vehicle over, for all they knew, it was not Wright driving it. So please don't give me his outstanding warrant as justification for pulling him over. They didn't know. They weren't looking for him. He had not just committed a crime.
EDIT: Wright was driving his brother's car. The police officer who pulled him over was a trainee and Potter was also in the car. He was pulled over for expired tags on his brother's car and also because the trainee noticed an air freshener strip hanging (a MN violation).
Plates can be run before a stop--either from a cop simply running plates he sees or from an automatic plate reader running every plate the camera gets. However, that only identifies the registered owner, there's no way his warrant was relevant if he wasn't in his car.
However, expired plates are a perfectly good reason to stop a car. Experience has shown that people with minor violations like that are very disproportionately likely to have committed more serious issues also.