John Thompson served 18 years in prison, 14 on death row.  Shortly before his scheduled execution, evidence of his innocence surfaced.  Evidence that was held by the prosecution, but kept from the defense.  When the prosecution tried to convict Thompson again, a new jury returned a not guilty verdict in 35 minutes.   In a New York Times op-ed, Thompson writes,

I just want to know why the prosecutors who hid evidence, sent me to prison for something I didn’t do and nearly had me killed are not in jail themselves. There were no ethics charges against them, no criminal charges, no one was fired and now, according to the Supreme Court, no one can be sued.

Read the whole thing.