My first bullet is part of the union contract for stewards in NYC hotels. The second and third are part of the union contract for Boston hotels. The first part of my fourth bullet happened at a colleague's hotel who [twice] caught an employee stealing, the second part of that bullet happened at the last hotel I worked at (and perhaps "physically assaulted" was a bit strong - for accuracy purposes you can reword it to "throwing an object heavy enough to hurt someone had their aim been better").
> Were they working from prison after criminal charges were brought?
Unless you have the encounter video-taped it's not worth bringing criminal charges against someone for stealing $100 or throwing a walkie-talkie. Especially since it benefits the hotel to let the union "convince" them to re-hire the person because that cost the union in future negotiating capital (i.e. at the next contract's negotiation the union will be reminded how "forgiving" the hotel had been).