Sadly, his murder will go unprosecuted as the people who did so have the whole backing of the legal system behind them:
What did they expect to happen when they set the cabin on fire? Did they think he would surrender?
This whole incident should serve as a warning to all mundanes who are outside of the protection of law enforcement. If the police are willing to burn one of their to death because of the horrible crimes he committed against you, then what hope do you have once they have cornered you?
Understand too that when I say Mr. Dorner was murdered, I mean it in the moral sense. I am sure there is some legal bullshit that basically states these officers are off the hook. But they are morally responsible for his life, regardless of what he had done to them. Human life is sacred and should not be taken so easily or so brazenly.