I was busy with furthering my education so my responses are late.
You do know there are other latin american countries other than Mexico? Most of them speak Spanish too. Many of the people are "brown and short". Some not, but many are.
You can get offended by the word Mexican if you want, I'll hand you a tissue.
I however wouldn't get offended if someone called me a White or Polish man, nor do any of my black friends get offended if someone/I call them black or African.
Now if I were to call him a beaner I could see where you're coming from. But I didn't so...
Apparently you knew the Mexican's car broke down.
But is that why the Black guy's car is in the middle of the road? Did the police know? I mean one way or the other there seems to be a very big screw up here.
If the guys car is broken down, why in the hell are the police all fucking hyper?
If the guy is wandering about with his car in the middle of the road for no reasonable reason, why isn't that a clue that the guy is irrational and may not dance like a puppet on command?
I've had many older people tell me wish they had logic class taught in school when they were kids.
A vehicle not running.
Person walking around the vehicle, in the middle of the road blocking traffic...
Logically the car is broke down and the person needs assistance.
So at the very least being a human, you go ask if they need help.
Not assume they're dangerous.
Not assume they're irrational.
Not assume they're a bad man due to how they look.
Some of your questions
@SlyPokerDog has already answered with his links previously.