And I guess that's exactly the challenge. Who "we" think are "the type of person who would be likely to do violence" or even posing "an explicit threat of immin

And I guess that's exactly the challenge. Who "we" think are "the type of person who would be likely to do violence" or even posing "an explicit threat of imminent violence" is not only subjective, but in our society very based on the social positions of the judgers and the doers. No doubt the police in the OP will swear that they had good reason to think that deaf guy was "the type of person who would be likely to do violence" and posed "an explicit threat of imminent violence"; if you take them at their word, then the police 100% of the time only use violence against such people because that's always what they'll swear they were doing. I don't take them at their word. Or even if they honestly believed that, they've trained themselves to see that in people who are not that, and they are terribly terribly wrong, And are in the majority of times they are using violence against people in the USA.