Not per se, but it was covering up to protect the football program. The primary motivation was to protect the image of the football program, so they could continue to recruit blue-chip players. So basically, Penn State, by covering up Sandusky's actions, were able to get players they otherwise would not have gotten. So what's the difference between that, and any other recruiting violation? The idea is to entice players to play for your school that otherwise would not have played there.
There is also a code of conduct and disciplinary rules in the NCAA bylaws. I also think it is up to a University to join the NCAA or not.