Tony always said he considered himself a "soldier" and the battles they did was essentially criminal against criminal. To a certain extent, I can go with this "reasoning." However, I think there are a few people he killed that was less in defense of or in favor of the family, and him just killing for the sake of his personal benefit. The two that come to mind are:
1. Chris Moltisanti - It seemed like Tony killed him just to get rid of him. Chris at the time was doing nothing against the family or Tony. 2. Ralphie Ciferreto - Yeah, they had their differences, but Ralphie was nothing but an earner and while Tony did not like him, Ralphie's death in my mind wasn't justified in the context of the mob life.
1. Chris was a liability. I don't think Tony would have killed him had Chris not admitted that he wouldn't have passed a drug test after they crashed--at least not right then. If Chris was anyone else, Tony would have had him killed instead of sending him off to rehab for his drug problem. He was still fucking up with the drugs and I don't think Chris would have sacrificed himself to do serious prison time if he had been caught. His loyalty to Tony and Cosa Nostra at that point was basically zero. I could see Chris ratting even if he hadn't got jammed up with a case or drugs.
2. Ralph was also a liability. He was plotting to take Tony out at one time and defect to NY as well, those two were on an inevitable collision course. Seemingly from way back. We didn't get the whole back story with Ralph, but clearly there was something else going on there between them. Tony doesn't like Ralph from the time he came on the show. With Ralph close to Johnny Sac before the mole joke, he was doing the same sort of the thing with NY Paulie was. Ralph asked to be put with NY, he threatened to kill Tony in front of Vito and Eugene, etc.
I think for Tony,the final straw was seeing that the tree branch destroyed the infant seat in the car. Along with that,and realizing that Chris could have killed him in the crash,Tony finally saw that Chris would forever be a junkie. I agree that Chris could have easily ratted Tony out if he had gotten hit with a narcotics rap,or the killing of the Cleaver writer,or a number of other charges. No way could Chris take a 30 or 40 year to life serntence'
As far as Ralphie I wouldn't consider that a killing in the accepted sense. Tony confronted him about Pie Oh My,lost his temper and beat Ralph to death. I don't think his intention in going to Ralph's was to kill him. Thing just got really out of hand fast.
