For myself, although on its face it looks open-and-shut, I can wait for the charge to be properly defined based on all the evidence they can find. Swift justice isn't always the best justice.
I hope the mob can wait, as well. If you want these people to be tried, then getting all the available evidence from every available angle is sensible. Cameras are going to give a picture of what happened. But also, you need to know if he followed (or thought he was following) his department's procedures, to get statements from his trainers etc. He is going to defend himself so you need information of that sort too. I would hope the law will establish facts before issuing warrants. I think he will be charged, but after the process is complete.
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