OK, so this is speculation on my part, based upon what I observe about human behavior. I'm not even talking about all the murderers, thieves, and rapists who wear badges, or the crimes against humanity committed "in the line of duty" due to enforcement of counterfeit "laws", but am talking about free-lance theft, murder, rape, and whatever else falls under the label of real "crime". (I am not talking about the peaceful, consensual, victimless, yet "illegal", behavior of others who are harming no innocent person, since those things are only "crimes" to the state, but not to sensible people.)
I have witnessed what happens when someone stumbles. If they are with one person, that person will normally try to catch them before they fall. If the stumbler is with a couple of people, though, often they will fall before the two people act. They each thought the other person would grab the tripping friend. It isn't a purposeful desire to watch someone fall, but is just a result of not acting because there is a question of whether someone else will take care of the situation. Even a slight hesitation is too much. I think the same principle applies to crime.
Crime thrives where people believe it is someone else's responsibility to take action. In big cities it is easy to think someone else will get involved, so you will mind your own business. This is even more true where there are a lot of cops. If someone is supposedly being paid to stop crime, it is even easier to turn away and let them handle it. In fact, cops encourage this poor behavior by criminalizing and punishing self-defense. "Don't be a hero. Call the professionals." Except that cops are under no obligation to protect you from crime. Try to sue the local LEOs after they fail to protect you from crime if you doubt me.
Stop contributing to the success of crime. Ignore the cops and take responsibility for your own safety. If it is your nature, take responsibility for the safety of those around you. Don't wait for some "professional", whose interests are not where you may assume they are, to step up and fix it for you.
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