"A good example of the corruption is your Godfather, actually, Sirius Black, who was sentenced to the magical world's worst prison without a trial, and has been there for years. There's enough holes in the official story that he's probably innocent, and he likely only ended up in prison because his family is old nobility that really fell from grace during his time. His family's enemies most likely saw the opportunity to eliminate the last of the Blacks and took it."