In my current game, the Iconians had obtained Xeno Ethics and chosen the Good alignment. Later in the game, the Iconians experienced the random event that causes them to become Evil. They started to behave Evil (I was Good and our relations started to degrade rapidly, for example) and other AI races would randomly contact me and say stuff like "we need to secretly work to oppose them before their darkness spreads across the galaxy".

THE BUG:
On all the reports screens the Iconians are still listed as a Good race. I am not sure what other aspect of the game as bugged due to this (ex: special tech availability, trade route restrictions due to the Evil trade routes UP resolution, etc.)