I've twice at two different jobs been in a situation that would have probably been better off being handled by the police and got reprimanded for it.
First one is when I was fresh out the Army and was washing cars at a dealership on the lot. Corner of 35th & Sandy. Guy started smacking up his girl right there 5 feet in front of me and a co worker. Knocked her down on the sidewalk and started kicking her. I looked up and all the car salesman and customers started to literally run the other direction. I was fresh out of the Military and was still in the National Guard, so lets just say I put my MP skills to use. Took him down and stood on his head til the cops pulled up. They drew down on me thinking I was the suspect, until witnesses told them what had happened. GM of the dealership instead of thanking me, brought me in his office and said he should have fired me.
As a know it all early 20s kid, (WE ALL KNOW HOW THEY CAN BE) I was pissed, but now I look back and totally understand.
Fast forward 7 years or so, when I went back to college, I worked at Music Millennium. I happened to see a guy sliding a ton of CDs in his coat pockets and went by the door, to make sure he didn't get away. He put up little fight, but the situation was quickly under control and I held him down til the cops showed up. All the hippies that worked there were mad at me. Said that I was just supposed to let him go and not confront him. Manager almost fired me, but quietly thanked me. Week later, while I was not working, somebody held up the register and he fired off a shot into the ceiling that ended up ricocheting into a co workers hand. Maybe had THE HCP been there he could have stopped that from happening as well.