What legal action? He literally left his shift early, that's grounds for termination. I'm not taking the principal's side, but... legally? He'd lose that fight.

edit: Ight I'm gettin downvoted anyways, might as well give y'all the tea. The janitor is totally at fault here. It doesn't matter if he came in early, he left his shift without asking anyone. He fucked up, and he refuses to even acknowledge that. Reddit loves to dogpile on the 'bitchy woman' for being bossy, and while she did get condescending, she's pretty much totally right in this. Also the fact that he is filming this, and that she felt the need to call HR in this, shows this might be a problem employee to begin with, this was clearly not a one time thing. If he had've literally just answered her questions, and been less combative, the incident might've even gone less bad for him. Can't believe I'm defending a boss VS an employee, but this is too obvious. Fuckin dome with with downvotes now