Michigan Assistant Attorney General Andrew Shirvell is threatening to sue the University of Michigan if it does not end its campus ban against him, AnnArbor.com reported.

The move comes after Chris Armstrong, the gay student Shirvell has attacked at his blog Chris Armstrong Watch, withdrew his request for a personal protection order against Shirvell.

Attorney Philip Thomas said his client plans to ask the university to lift its trespass warning and allow Shirvell back onto the university's main campus in Ann Arbor, where Armstrong serves as the president of the Student Assembly. If denied, Thomas said a lawsuit would likely follow.

Shirvell led protests against Armstrong at his home and at university events. At his blog the official accused Armstrong of preying on impressionable freshman, of being “Satan's representative on the student assembly,” and labeled Armstrong a Nazi, a racist, a liar and an elitist.

The case attracted nationwide attention when Shirvell appeared on CNN's Anderson Cooper 360 defending his right to campaign against Armstrong's “radical homosexual agenda.”

Shirvell, who is currently on a leave of absence, faces a November 5 disciplinary hearing.