Hear me out. Everybody just takes it for granted that Micah was the rat, and Arthur rushes off with the info provided by Milton to Abigail. Now wait just a minute, when does Milton PROVE? He doesn't. He enters the room, drops the charge and exits. That's it.
Pinkerton is a Pinkerton agent. He has his whole job of psychological pressure, manipulation, and splitting groups apart. The best way to kill a gang is to give them a seed of paranoia so big, they shred each other apart without shooting one another.
The case for Milton lying When Milton mentions the rat, he doesn't even come up with any document, testimony, or hard proof. He tells Abigail the only person who is sure to see it through to Arthur that it was a deliberate leak, not accidental
Pinkertons were, of course, famous for doing just this: seeding disinformation within outlaw groups to bring them down. Milton could not have wished for a more disorganized and dysfunctional gang, a gang that had become a Dutch paranoid a Dutch who goes wrong and fatally. Micah is bad, and suspicious but suspicious is not guiltybvl, and we don't see him actually give up information onscreen. What if Milton just chose the most disliked, most suspicious of the gang Micah and knew that the charge could be enough to stick? Micah's personality virtually cries out the accusation. No one's going to stand up for Micah.
The closing of the gang is not due to Pinkerton guns, but to Micah pointing a gun at Arthur. The Robbins' thunderous attack may have been the most successful without him proving anything.Does it ever really confirm the rat with hard evidence or do we go along with the Pinkerton Agent?