One more example.
Generally there are two types of people in society. Civilians and predators. By civilians, I mean ordinary people who just go about their business
without thoughts of exploitation.
Predators are driven to exploit others. Like a wild animal, they see a weakness, it activates their prey response. Some manage to suppress this urge,
but many do not. Some redirect this urge into socially acceptable venues, such as sports.
A predator might not be overtly aggressive; I'm talking about a behavior that is central and it might be expressed passively (passive-aggressive).
Now criminals are mostly 'predators'. Many military career types are predators. Many police are predators by nature.
Thus, for this and for other reasons, cops and criminals are not that different. They share many traits and they depend on each other.
Without criminals, cops are generally just doing traffic duty. Without criminal informants, cops don't have that information flow.
Now, say you were a victim of a crime by a CI (confidential informant). If it was a very serious crime and there were witnesses, a cop will give up
his CI. But say the crime is less serious. Hit-and-run with minor to moderate injuries might be one example.
If the cop knows who did it (say by the car's description), is he going to give up a major source of information just to give justice to the citizen?
Maybe, maybe not.
As we've seen, there's no legal bases for cops 'protecting' anyone. It's more-or-less optional or situational.
Now, say you dispute the cop on this. Now his self-protection instincts kick in and they start looking for reasons to prosecute the victim. In fact,
many cops will pull things out of their hat if a citizen is not fully cooperative, even if the cop has no legal basis for stopping or questioning
them.
They are experienced at getting what they want and being natural predators and having 'training' will not back down.
While not all cops are predatory in nature, many soon start exhibiting those traits. They 'learn' from other cops.
This is one way you can understand why it's better to avoid interfering, reporting on, or making complaints. They have your name linked to your
license plate. That's an easy entry point for cops to start the harassment and intimidation if they please.
2 cents.