First degree means you had intent. That intent can be formed in an instant. When Dunn RETURNED to his car to GET HIS GUN that is intent. He could have just returned to his car and been upset.
As much as I am not fond of mouthy youth, I have never thought that pointing a gun at a car full would end well
He had several options....could have just returned to his car.....or he could have notified L/E about the noisy kids, and let them handle it.
My understanding is that Dunn was parked next to the teens and never left his car prior to the shooting.
Angela Corey argued the fact that Dunn reached into his glove box, removed a handgun then chambered a round before shooting met the 'intent' requirement for the first degree murder charge.
Returning to your car and getting your gun does not prove intent to murder. It could prove intent to scare, attempt to detain until police arrive, etc.