Ray Rice
Rice changed the landscape of the NFL but not for a good reason. The former running back won a Super Bowl with the Ravens but that’s not why he’s on this list. He viciously assaulted his fiancee and dragged her unconscious body from an elevator (via Baltimore Sun).
However, the NFL initially suspended him for just two games before they realized the error of their ways. Then they slammed him with an indefinite punishment. When they declared he could play again it was too late because nobody wanted to tarnish their brand by signing him.