The public power should prevent crimes or bring them to court. That is clear. But there is something else too.

What is it?

Permitted actions also have results for others. I may do what I want with my property. But it often touches other people and shared facilities.

An example:

I stack wood in my yard. I have every right to do that. But the pile stands close to my neighbor’s house. If it catches fire, his house burns too.

In this way, my private action turns into a chance event that I no longer control. It can harm others and do them wrong.

Summary: Not only crimes do harm. Permitted private actions can also hit others. So they concern the public power.