It may be a good thing for them to know that at any point in time they could be killed. Previously they would be able to count on a sort of code of escalation where they would know exactly the kind of response from people they would get. They would know exactly what kind of danger they were in and could count on having both the authority and the means to outmatch any level of violence.

In other words these scenarios would play themselves out with the police always understanding what kind of threat they were under based on what was going on. This might change things a bit, as it means that the police could be doing anything at all including just hanging out and still be under the threat of getting gunned down. This thought is probably terrifying to them individually anyway.

This shooting also has the potential to change the perspective for some into seeing themselves and their communities as at war with the police. Not as a kind of metaphor in that they are in serious opposition to each other, but that the police are an enemy, and if there are the means, they should be wiped out. That it doesn't matter what an officer is directly doing at the moment, but what they do as an institution that warrants this kind of response.

Now there is no difference between a cop that is abusing or assaulting someone and a cop that is wandering around bored, or just getting off of work. The perspective takes into account the entire institution rather than waiting for an instance of brutality to condemn or defend one's self from. Before they were frustrated by instances of brutality themselves, now they have directed their frustration at the institution that is responsible. This is probably the better perspective.