The only way to get them to stop defending Paterno is to openly confront them on Facebook, Twitter and in real life, by first asking politely for them to reconsider, and when that doesn't work, employ other options, so that at least those around that person know he or she will be challenged in public for defending the indefensible.
But he grew old, this knight so bold / And upon his heart a shadow / Fell as he found / No spot on the ground / That looked like El Dorado.