Originally Posted by Silent_Guardian
It is utilitarian because Dent was on a rampage, murdering the guilty and innocent alike. Not allowing him to continue, regardless of the means, results in a positive net utility to society; take one life to save countless.
Right but that's not the circumstances surrounding Harvey's death. Bruce didn't sit back and make the calculated decision that killing Harvey would result in a net positive for Gotham and then go assassinate him.
Harvey had murdered people and was now pointing a gun at an innocent kid - the shove wasn't to end Harvey's killing spree, it was to save the boy.
Put it this way, if Harvey hadn't created that situation there's no way Bruce would be hunting him down with the intent of killing him.