If you're a member of a group who perceives themselves as oppressed, accurately or not, increase the panic by at least an order of magnitude.
It could well be the differences between Australia and the US, but we had a thing we called a Whome Patrol. You see a group who are just hanging around looking a bit suspicious, so you pick one on the edge of the group, there's always one with no one within a few feet of them, and point right at him and say, "I'd like a quick word with you?" It matters not if there's no one within two feet of them or twenty-two feet, they always look to their left, their right, behind them, then tap their chest and ask "Who, me?" When you nod they come over, you quietly ask what they're all up to, get the gen - usually it's something innocent like waiting for Jerry or Joe etc. or killing time until the next movie theatre session. It's how they react while you talk to them that's the main thing you base your judgement on.
What's amazing is when you find out later what they tell their mates you spoke about, it's never what you actually talked about.
In any organisation there are real good ones, real bad ones, mediocre ones, and average ones, and it's just the luck of the draw which one you get on any one day. Thus is the wisdom of an ex-cop who's currently pissed off due to being jerked around by a zealous arse hole of a cop.