Actually the book explains ( it's been a long time since I read it, so don't hold me word for word ) that a member of another mob family associated with the Corleone's had been found guilty of murder and was facing the death penalty, or life in prison. So Vito made them an offer : Being that this family member was already going away for life or facing the death penalty, The Corleone's would take care of his Immedeate family finacially in exchange for this person confessing to Killing McClusky and Sollozo. This is how Michael was cleared of all the charges that he was facing upon his return to the states.


Don Cardi