Word of the day: spoliation (n) - the action of ruining or destroying something.
When you intentionally destroy evidence relevant to a legal proceeding, you are spoliating evidence. In general, if a court finds that you spoliated evidence, it will sanction you with a "negative inference." That is to say that the court or jury will be allowed to assume that whatever was in that evidence, was unfavorable to you.
We will never know what was in the text messages that Urban Meyer deleted. Ohio State should have done the right thing and terminated Meyer for knowingly employing and retaining a coach who was a known abuser and an all around bad guy. If they had, they would have held a strong hand going into any wrongful termination suit: spoliation. The judge and the jury would likely have been able to infer that Urban Meyer had deleted text messages because he knew that they contained facts which would have been unfavorable to him.