In The Departed (2006), after hearing from Dignam that Myles Kennefick, who stole 20 microprocessors worth 100 grand each from the Mass Processor Company, was dead, Sullivan visited Mrs. Kennefick to question her:
Sullivan: You wanna help catch the people...who forced your son to do a robbery and then killed him?
Mrs. Kennefick: Allegedly. If he was killed, he probably did something wrong.
Sullivan: But not the robbery. That's not wrong. He did something else wrong?
This statement suggests that Sullivan thinks that committing the robbery isn’t morally wrong or deserving of punishment.
If Sullivan is a staff sergeant, why does he believe that the robbery was not wrong?