Steves ex-boss

My friend Steve had an ex-boss who harassed the staff, the customers and Steve. After he was fired unjustly he wrote a detailed letter: (1) giving a blow-by-blow description of how the ex-boss harassed employees, customers, and Steve. (2) and the reason that Steve wrote the letter to the CEO is because the CEO needed to know how this ex-boss operates.

Right after the CEO received the letter (at his house) the ex-boss had a review and was put on warning. My question: Since the boss was put on warning how is she monitored? (Keep in mind she is a manager in bank branch and her boss and the higher ups are not there every day).

I'm sure they'll just monitor through her employees by checking up on them and asking if there have been any recent problems.

I think they just put it on file and if another issue comes back, they fall back on the whole issue that was reported and say 'She has been formally warned about this behavior and needs to be escorted' type thing.

I think a lot of time 'warning' means that if they get anymore complaints about that particular person, then more disciplinary action will be taken. So if a customer complains or something, there's a better chance the boss will get fired.