Is he doing it because the priest spoke out? It's unclear to me just what the situation you're describing is.
He has spoken against the abuses and dissent here in sermons and talks around the diocese, as well as numerous letters to the editor and guest columns in our local papers. He has been (rightfully) accusing the bishop of misfeasance both in failing to fight the homosexual agenda at Penn State as well as in the diocese in general.
The bishop has been trying to trump up canonical charges against him for years. This bishop is demonically vindictive against any priest or layperson that challenges him publicly.
Recently this priest's new parish assignment became public knowledge before it was "officially" announced in the bishop's annual parish assignments letter. The bishop considers this a gross breech of confidentiality, and combined with this priest's past public statements, is attempting to remove the priest's faculties to say mass publicly, hear confessions, preach, teach, etc.
This combined with the fact that this priest's brother is carrying on a newspaper ad and billboard ad campaign against the abuses here has our bishop in a bit of a rage.