My copy is in Palermo so I'm going off of memory.
In the opening scene, an intercity bus arrives in the dusty town square, and everybody gets off.
You do not talk to cops.
Everybody knows who the hard men of the town are, and their behavior makes it clear when it really is best if you suddenly find something interesting in the other direction.
This is how codes of silence are sustained from personal life into institutions. People know when to look away, to minimize the amount of actual lying.