Why did Ryan Philippe's character SPOILERS...

We're supposed to see an officer who's new to the job. He's new and not racist. He checked the producer at the initial stop so he knew him. At the 2nd incident, even though the producer was verbally aggressive, he knew to defuse the situation especially because he knew him from the initial stop and he wanted to avoid a situation where his trigger eager colleagues wouldve shot him because he's black. But remember he's kinda new, based on what officer Ryan told him ("wait a couple more years and you'll see"). This scared him. He's also alone in a patrol car with a radio malfunctioning.
And the scene in question... he was alone, picking up a black man hitchiking at night as to prove to himself that he's not racist. But at some point he started to feel unsafe especially because the passenger started laughing with no reason. He interpreted the situation wrong and acted without thinking. That was an unintentional killing - manslaughter I think. He became a murderer when he torched his car to get rid of the evidence.

Also, in order for this situation to have been avoided particularly with its very tragic outcome...

What should both the driver and passenger have done? Should the guy laughing have apologized and immediately confessed to having the same statue as him? Should Ryan Philippe's character have given him a second chance? Is laughing for no reason REALLY a suspicious, disrespectable and even an offensive thing to do?

Was either of the characters at one point in the right? Was Ryan Philippe WRONG to tell him like that to get out of the car, and only because he laughed out of nowhere like that? Was Anthony wrong not to apologize and get angrily defensive? Cheers.