They may have the authority, but there are still procedures that must be followed. If they didn't follow TN ellection laws, then no, they can't just remove her.
I don't think for a minute that Ford didn't cheat to win the election, but there are still laws that have to be followed. I guess that's what the judge is determining and if she doesn't follow the law (like the FL Supreme Ct. in '00) then she will hopefully be overturned at a higher level.