I didn’t pay the train at the Omni Station (a black neighborhood). The Policeman noticed it, and ran after me. He couldn’t get me, because the train took off.

Neither I paid at University Station (University of Miami's station, a white, professional neighborhood). The policeman noticed it because he was in front of the gate. I was to show him the card— although he never asked me to show him anything—, but he didn’t bother to look at it. He offered me Coffee, and a good morning.

This is known in Journalism as FALSE LIGHT, where one creates these kinds of situations to see how prejudged—in this case—are the cops.

In other words, good luck with the perception of the next person you are about to face.