JoePa covered up nothing. He reported the incident to his superiors, one of whom managed campus police, and made sure McQueary followed up. Sandusky was not a Penn State employee at the time, and was banned from campus facilities shortly after the incident. Paterno did not do more, and said in retrospect he wishes he did more. We also still don't know what McQueary actually told Paterno, beyond "something of a sexual nature" - McQueary has stated several times under oath he did not give Paterno the details because he was embarrassed.
That said, nobody seems to think through what Paterno *should* have done further after reporting the incident. Called the police? He thought he was doing that by reporting to Schultz. Called them to ensure the investigation was continuing? Perhaps, but he'd then be condemned for interference with official acts, and remember Sandusky wasn't his employee.
There was a coverup, alright, but it was from Schulz, Curley, and Spanier, along with the Second Mile charity management and board, HIS ACTUAL EMPLOYERS and the source of those victimized kids. That's where your contempt should lie, Paterno was a bit player by comparison.