[Superman]

In my state, the "employment at will" doctrine applies. This means that employers can grant or take away any employment relationship at their whim. A manager can suddenly fire everyone with a moustache and replace them with members of his municipal basketball team. This, in the dark blue People's Republic of Washington State. He/she can only get in trouble by discriminating against a protected group and only an idiot would say this was the reason for their action.

This sounds very much like a turf tussle. I can only imagine how unlikely this sounds to most of you but on rare occasions, it can happen.

The smart play might be to advertise the position and then rehire your pick. In my office, which is a state agency, we have a cumbersome process which surely must come as another surprise to you guys. That said, I participate in appointing the interview panel(s) which then forward the best candidates (usually 3) to me for decision. At that point it is totally my call, regardless of the objective (education, experience, etc) facts. I choose based on what I think is the "best fit" and the matter is closed. It's a PITA that takes a long time but in the end, any appeal to the decision or the process would be fruitless.