I think Chauvin intended to kill him. I suspect Floyd either kicked him while he was in the back of the car, or Floyd had something on Chauvin. If he killed him because he kicked him, its second degree murder. If he planned to kill him even a few second in advance, its first degree remediated murder.

The important thing to consider is that for over five minutes Floyd never moved, and Chauvin had to be forced off of him by paramedics long after no pulse was detected. Chauvin wanted to make sure he was dead, maybe he is just a sicko, or maybe he had a reason. If you ask me Floyd was pitiful..