There is the old way aka the lupara bianca,if there is no body,there is no crime,lok to the hoffa case: 40 and over years and nobody sentenced for his murder.
The guys the FBI suspected of the Hoffa disappearance were hounded by the FBI ever since. Tony Pro died in jail, I believe Russell Buffalino did as well. Frank Sheeran died a free man, but spent much of his life behind bars.
Provenzano was convicted in the Anthony Castellito murder and sent to prison,Bufalino went out of jail in 1989 after a 10 y sentence (and only because was the bufalino boss) Frank Sheeran made 9 years and was released due the poor health in 1991 and the other detroit mobsters made few or none time in prison and died free and old.
