Apparently, at least at Indiana University, it extends within your office, but not your window or on the hallway side of your door.
A campaign sign in an IU professor's office is acceptable, while a sign in the window facing outward is iffy, and a sign in the lobby of an academic building most likely is against the law, school officials said.
Posters, buttons and bumper stickers from individual staff or faculty members are allowed, but the university as an institution cannot make political endorsements.
It is all about the appearance of governmental endorsement. If it looks like the university is sponsoring the statement, no dice. If it is only personal ... fine. The lines here are pretty small. In your window facing in ... fine. In your window facing out ... fired (potentially). Ahh the joys of political season in governmental entities.
Photocredit: Mr.TinDC