From an AP obit by Alanna Durkin Richer headlined “Ex-Mafia boss ‘Cadillac Frank’ Salemme dies in prison at 89”:

Francis “Cadillac Frank” Salemme, the once powerful New England Mafia boss who was serving a life sentence behind bars for the 1993 killing of a Boston nightclub owner, has died, according to the Bureau of Prisons.

Salemme led the Patriarca crime family in Boston in the early 1990s before helping prosecutors convict a corrupt FBI agent after learning that other mobsters had been talking about him to authorities.