Mob bosses James Marcello, Joey "the Clown" Lombardo, and Frank Calabrese Sr., along with Paul "the Indian" Schiro were all found guilty of racketeering conspiracy that included finding them guilty of the murders.
Former Chicago policeman Anthony Doyle was also found guilty of racketeering.
Calabrese's son Frank Jr. and brother Nicholas testified about his preference for strangling his victims. Nicholas also recounted Calabrese's roles as well as his own in the 1986 slayings of Las Vegas mob figures Anthony and Michael Spilotro that was later depicted in the movie "Casino."
Lombardo, 73, who lived up to his nickname "the Clown" with his quips during the trial, testified that he was only a "hustler" and had never been a member of the Chicago mob.
Lombardo's lawyer said his client changed his ways while serving time in the 1980s for bribing Nevada Sen. Howard Cannon and later took out a newspaper ad trying to dispel his reputation by asking anyone who saw him commit a crime to call his probation officer or the FBI.
A third Spilotro brother, Chicago dentist Pat Spilotro, testified how he helped capture the fugitive Lombardo who had shown up at his office for relief from a toothache.
The defendants could face life in prison, as well as millions of dollars in fines.
