Question: The Valachi hearings were named after which American gangster and first member of the Mafia to acknowledge it existed?
Sentence (from "Joseph Valachi"): Joseph Michael "Joe Cargo" Valachi (September 22, 1904 – April 3, 1971) was an American gangster, notable as the first member of the Italian-American Mafia to publicly acknowledge its existence, and credited with popularization of the term "Cosa Nostra".
Relevant evidence: Yes