Background
Hennessy was born in Montreal, Quebec, and educated at Saint Michael"s High School and Luke Callaghan High School.
Hennessy was born in Montreal, Quebec, and educated at Saint Michael"s High School and Luke Callaghan High School.
He was first elected to the Ontario legislature in the 1977 provincial election, defeating New Democratic Party candidate Iain Angus by 2,256 votes in Fort William. Hennessy was re-elected without difficulty in the provincial elections of 1981, and 1985. He served as a backbench supporter of the Bill Davis and Frank Miller administrations.
He lost his provincial seat in the 1987 election, falling to Liberal Lyn McLeod by 1,463 votes.
He died in 1991, less than twenty-four hours after attending his last council meeting. The legislature paid tribute to Hennessy on March 18, 1991.
Mike Harris, then leader of the Progressive Conservative Party, credited Hennessy with bringing "a touch of the common person back to the caucus discussions".
He served in the Legislative Assembly of Ontario from 1977 to 1987, as a member of the Progressive Conservative Party. He was a member of Canada"s 1936 Olympic boxing team, and was inducted to the Canadian Boxing Hall of Fame in 1977. Hennessy was a Roman Catholic, and a member of the Knights of Columbus.
Hennessy was a member of the Fort William city council from 1962 to 1969, and served on the Thunder Bay city council for seven years after amalgamation.