Ferriola began his career as a protégé of the late mobster Leonard “Fat Lennie” Caifano. Fat Lennie was Marshall Joseph Caifano‘s brother.

In 1970, Ferriola and four other mobsters were convicted for conspiring to operate an interstate gambling ring. He was sentenced to five years in federal prison, but only served about three years. He later became one of the Outfit’s top enforcers, working in particular as an enforcer for Sam Giancana. A 1989 article in the Chicago Tribune reported that federal agents had described Ferriola as a “cold-blooded terrorist” and as one of the most feared men in the mob.

During his mob career, Ferriola was the boss of his own street crew, the Cicero Crew, based in Cicero, Illinois with Ernest ‘Rocco’ Infelise serving as his underboss. This crew was involved in activities such as extortion, loan sharking, and bookmaking. To protect these enterprises, they resorted to bribery, corruption, and the occasional murder of someone who was a threat to their operation.

In 1985, Ferriola became operations chief for the Chicago Outfit. After suffering health problems and dealing with legal inquiries by the Federal Bureau of Investigation and the Internal Revenue Service, Ferriola was replaced in late 1988 by Sam “Wings” Carlisi.

At the time of Ferriola’s death, federal prosecutors were in the process of seeking an indictment of Ferriola on racketeering charges.