hey guys. im not sure if anyone has mentioned this but when angel, riley, burt, and kalani are driving to the hospital, angel mentions that he has the silenced mp5 from the colony. this may be the gun that was used to kill pippen. if so, then this is a big step towards angel possibly being the rat/murderer. id also like to point out that if its not the gun, then the gun used has to be burt's barreta. the person who has it is possibly the rat/murderer according to Arthur LaMarche, who pointed out that only two silenced weapons are in the towers possession.