Tony has always looked out for number one - no matter what. If he is indicted, which is likely with Carlo's flip, I can see his defense team setting up a "Silvio was the real boss" scenario. With Silvio in the coma or dead, what a perfect defense to exonorate Tony Soprano thus he "gets away with it" yet again! Remember,the burden of proof is on the Feds. Nobody is alive to back up Carlo's testimony, all the other informants are "gone"...Big Pussy, Adriana, Jack Mazzarone, etc..Reasonable doubt can be easily created by a good defense team.
I think you make a good point about reasonable doubt however i disagree because the FBI has Carlo who is a high ranking captain in the family. Throughout the show the FBI never had a witness like Carlo would be. Sure they had Pussy but he wasn't given them much and plus the feds were more concerned with Junior at that point. they had Ray Curto and were very close to having a good case until Ray died. Carlo is given order directly from tony so he would bury him
