I was wondering if protection from evil defended against song of discord.
This spell causes those within the area to turn on each other rather than attack their foes. Each affected creature has a 50% chance to attack the nearest target each round. (Roll to determine each creature's behavior every round at the beginning of its turn.) A creature that does not attack its nearest neighbor is free to act normally for that round. Creatures forced by a song of discord to attack their fellows employ all methods at their disposal, choosing their deadliest spells and most advantageous combat tactics. They do not, however, harm targets that have fallen unconscious.
Protection from evil only works on charm and compulsion effects where the caster is able to exercise control over the target, such as command, charm person, or dominate person; it doesn't work on sleep or confusion.
I was thinking it does NOT defend, because song of discord is basically killer confusion, and you can attack the caster if they're nearest. But I was not sure because of song of discord's language about turning on fellows and tactics selection.