[user104658]

I actually do think that in this case it comes down more to the policing methods than anything else. Watching the video, and going by what I know of standard US police tactics, the officer won't be found to have acted wrongly; she was armed, she was about to use it on someone else, police in the US are taught to shoot the armed person in that scenario.

However, in the UK (and in MANY other countries) this entire situation would have been handled differently, they're trained to disarm and apprehend people with knives and other weapons without anyone getting killed, and in this exact scenario it's likely that NO ONE would have died. To people who think the officer had no choice; does the UK police not deal with knife crime every single day? Do not they do so every day without firearms? And are people often killed because of the lack of guns?

Basically I'm saying that in most places, this situation (teens getting violent, weapons being present) would have been handled differently by necessity and thus it is perfectly possible to handle these situations without shots being fired.

Again it comes down to police in the US being trained too quickly, their methods being too basic, and the constant "one size fits all" solution of using their guns. The UK police have tonnes of training in how to handle violent situations without it ending badly. In the US it seems to be;

1) Point gun and make threats,
2) If that doesn't work pull the trigger.