I am still reading through all the recent posts on different theories and I'm nodding agreement to everything - the only theory I would dispute is the idea that TM did not strike a blow. I agree absolutely that Molly initiated the attack and Tom's "intervention" in the "donnybrook" involved establishing an alternate scenario. However, as there were two weapons used, and presumably two types of injuries, LE might have decided there were two attackers. LE was very quick to dismiss the presented story - one attacker in self-defense, so I think there is some clear forensic evidence of two attackers.
Alternately, they quickly decided that Molly was the sole perpetrator and they charged both of them to put the heat on her father to tell the truth - hoping he will reason that if he can't save his daughter from jail, he might as well save himself. This is more of a defense lawyer's strategy than a LE strategy, so I think there is something linking both Molly and Tom to the weapons and injuries.
Alternately, they quickly decided that Molly was the sole perpetrator and they charged both of them to put the heat on her father to tell the truth - hoping he will reason that if he can't save his daughter from jail, he might as well save himself. This is more of a defense lawyer's strategy than a LE strategy, so I think there is something linking both Molly and Tom to the weapons and injuries.