""If you voted for Obama … seek urologic care elsewhere"

Cassell may be walking a thin line between his right to free speech and his professional obligation, said William Allen, professor of bioethics, law and medical professionalism at the University of Florida’s College of Medicine.

Allen said doctors cannot refuse patients on the basis of race, gender, religion, sexual orientation or disability, but political preference is not one of the legally protected categories specified in civil-rights law. By insisting he does not quiz his patients about their politics and has not turned away patients based on their vote, the doctor is “trying to hold onto the nub of his ethical obligation,” Allen said.

“But this is pushing the limit,” he said.