wat wud i say 2 d person-in-charge that his/her subordinate done a wrong thing but doesn't want to.?

The person i am referring to is a NEW member of the company with a position higher than the old employee. The one who went wrong is in the company for many years. It seems dat she doesn't want to make this old employee uncomfortable being her subordinate. And, it is proven that something went really wrong. Well, i am a man and they are both women...i don't really know if they are covering up samting to protect their integrity in the company?.