How is Morris different from the other scowrers? What is the significance of the secret he shares with McMurdo?

Morris is one of the elderly brothers, and he is different because he disapproves of the Scowrers' violent tactics and warns that they must be careful in their targets. He seeks out McMurdo as an ally, and he later provides the information about the Pinkerton spy to McMurdo, thereby unwittingly providing it to the spy himself.