William Daddano Sr. (1912-September 9, 1975), also known as William Russo, was a top enforcer for the Chicago crime syndicate, also known as the "Chicago Outfit".

Born in Chicago, Illinois in 1912, Daddano was a member of the Forty-Two Gang, a local street gang based on West Side neighborhood of Maxwell Street, where he was noticed by Chicago Outfit leaders Sam Giancana and Sam Battaglia . By 1936 Daddano had already accumulated an extensive criminal record, having been arrested on numerous charges, including nine counts of bank robbery, larceny, and auto theft.

In 1944 Daddano was arrested for an attempted West Side robbery of three million war ration stamps. While the robbery was suspected to have been backed by the Chicago Outfit, Daddano refused to name his accomplices. Following the end of World War II Daddano had become a leading enforcer for the Chicago Outfit, suspected in over twenty murders, and controlling illegal gambling operations in the Chicago suburbs of Cicero, Berwyn, and DuPage County.

Daddano was arrested in May 1966 for the hijack of $1,000,000 silver bullion but was later acquitted. However Daddano was later arrested by an FBI Task Force led by Vincent Inserra and arrested for conspiracy to rob Franklin Park Bank, planned by Daddano six years earlier, and sentenced to fifteen years imprisonment at Marion, Illinois federal penitentiary, where he died on September 9, 1975.

Further reading

• Nash, Jay Robert, Encyclopedia of World Crime (D-J) Vol. II, Crimebooks Inc., 1990.