Mercurius
Legend
Given that D&D is fantasy, you could add some sort of mystical or magical element to why they are outlaws. Maybe they are all "marked" in some way, perhaps part of some prophecy about the overthrow of the dark overlord? Or maybe the empire or nation they are in outlaws magic and they all have some kind of innate magical abilities? Or maybe they all have some sort of inheritance, of the blood of a lost line of kings or sub-race that is viewed as a threat in some way?
For a different take, you could set for the high seas and have them be pirates.
If you wanted to start out at higher level, they could all be amnesiac and not know why they are outlaws, only that the law really wants them badly. Then you could drop bits and pieces of memory, filling in some kind of intricate back-story.
You could also really have fun with NPCs in this sort of scenario - maybe a series of bounty hunters that come after them, a recurring guard captain or inquisitor type that is their nemesis, etc.
For a different take, you could set for the high seas and have them be pirates.
If you wanted to start out at higher level, they could all be amnesiac and not know why they are outlaws, only that the law really wants them badly. Then you could drop bits and pieces of memory, filling in some kind of intricate back-story.
You could also really have fun with NPCs in this sort of scenario - maybe a series of bounty hunters that come after them, a recurring guard captain or inquisitor type that is their nemesis, etc.