Freedom of speech and free artistic license are of the utmost importance, but you also wouldn't want to put any faculty members in a compromising situation.
Authors of historic fiction are able to take some degree of artistic license with the periods in history about which they write, as long as they don't attempt to rewrite the course of history.
One of the reasons normal butterfly tats are so popular is because you can take so much artistic license with wing shape and colors.
The artistic license taken in the series is similar to that of True Blood which has veered from the Sookie Stackhouse novels upon which it is based.
Tho I've taken artistic license with some of them.