I think the public in general is not a threat - until someone takes charge of them and makes them one. A mob is only as smart as the dumbest member (write that down, in ink). Convincing a mob is easy, convincing individuals is hard - there is something about being anynomous that emboldens some.

I see a family coming at me, I semi-doubt the first reaction from them will be to use violence. On the other hand, three young males - they are more apt to be a leader and two stooges, so I act differently to them than mom, dad and junior. Common sense.

Look at the group as a whole, determine who makes up the group, who the alpha is - is it a gang leader, or a preacher? Makes a world of difference sometimes (notice, sometimes).

I've been on humanitarian missions. Each group of refugees was treated somewhat differently, depending on makeup and circumstances. I was not quite as "nice" to able bodied people pushing to the front of lines as I was the sick/elderly.

Treat people with kindness, but don't let your kindness be miscontrued as weakness.