To chime in about Ace and Dragon:
Ace was definitely a pirate, he flew the Jolly Roger, captained his own crew, the works. But him being the son of Roger was the paramount "crime" he was being executed for. Even if he lived a humble life as a fisherman, if the WG learned who he really was and where he lived, he still would have been dragged to Marineford to be executed.
As the WG operates on the "sins of the father" style of law. So, Ace simply was an enemy of an injust world from day one.
Dragon, had Garp not saved him, would have likely been tried as a would-be pirate and executed as the WG is corrupt and authoritarian.