So what you’re saying is the police while seeing him a car multiple time before the incident DIDN’T not the license plate and ID the owner and get a breakdown?
The fact is that we don’t know now all that they knew up to the shooting.
I don't know that the police would even bother cross-referencing a motor vehicle record with a criminal database anyway. They have no way of knowing if the guy sitting in the vehicle is the one who actually owns it.