Post History

It is not so strange. The police as we know it in Western democracies is something that became necessary with the introduction of said democracy. Prior to democracy, the laws would be enforced by those with the power to do so - a King, the aristocracy, the wealthy etc. Often at their own leisure.

There were always laws,  but there wasn't always **_the concept of everyone is equal to the law_** - this is a relatively recent thing and goes hand in hand with the democratic principle of one person, one vote. 

In non-democratic societies, class, wealth and gender will affect your chances of winning the case, as much as evidence of the crime. We can look at modern despotic societies or historical ones in the middle-ages/renaissance. In historical despotic societies, there were no courts but there would be elders/lawmen/noblemen acting as judge and you would have to plead your case yourself. Meaning that skills in rhetoric and general education also affected your ability to win.

However, those who act as judges in a despotic system had peer pressure on them as well. Most rulers no matter society would like to be regarded as just - it's always regarded as positive trait in all cultures. So in case they were prone to nepotism/favouring certain parties, they risked losing face and trust. Essentially the very same thing keeping politicians in check in modern democracies. 

In modern despotic societies, there tends to be police and a court system, but very much corrupt. In such counties, you would rather have "all animals are equal, but some are more equal than others" to quote Orwell/the Animal Farm. If there is no interest in the court case by the ruling party, of you don't challenge it and that it doesn't need to make an example out of you, you might even face something resembling a fair trial. But then the ruling party also makes the laws, so the system is already corrupt at the point when the laws are written.

Evidently, police must not exist for a society or legal system to somewhat function. But a despotic law enforcement is just arbitrary, unfair and corrupted. 

You must have a non-corrupt neutral police force and similarly non-corrupt neutral courts, in order to exercise the concept of everyone is equal to the law.

As an example we can look at the many court cases against Donald Trump recently. Or against da Silva and Bolsonaro in Brazil. To make the ruler accountable for breaking the law would have been unthinkable in a despotism or feudal society.