February 2 - Chicago labor racketeer Maurice Enright is killed. Timothy D. "Big Tim" Murphy is suspected in his slaying, but is released for lack of evidence. Although suspected by authorities to have involved the Torrio-Capone organization, Chicago labor union racketeer James Vinci is eventually convicted of his murder.
April 15 - The Slater and Morrill Shoe Company is robbed of $15,776 as a paymaster and guard are killed, supposedly by the Morelli Gang, however Nicola Sacco and Bartolomeo Vanzetti are convicted of the robbery and are later executed.
August - In a daring daylight robbery, Timothy D. "Big Tim" Murphy and his gang rob a mail train of $400,000. Murphy is indicted in February 1921, and convicted in November 1922.
October 2 - Giovanni "John" Vitale, Detroit mafia leader dies.
December 26 - Monk Eastman is killed by a corrupt Prohibition agent.
Matthew Ianniello "Matty the Horse", loan shark and labor union racketeer for the Genovese crime family.
April 13 - Roberto Calvi, Banco Ambrosiano chairman and mafia associate.
May 8 - Michele Sindona, Italian mason and mafia associate.
September 27 - Carlo Alberto Dalla Chiesa, Italian carabinieri general.