system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: What is "citizen arrest" and when is it okay to use it

I've heard of the term before but I dont know exactly what it means. Today some crazy lady came up to me in a parking lot saying I stole her parking space and that she was going to put me under citizen's arrest and call the cops. I ignored her but it got me thinking about what it actually is and when it can be used.
gpt
Generally you have to actually witness, beyond any shadow of a doubt, a felony take place.  It varies between the states though.  One thing that is important to remember is that, unlike cops, you have zero legal protection.   If it turns out you were wrong, you are getting sued and you might go to jail.  If you hurt them, that's a lawsuit waiting to happen.  Just call the cops.