He attended high school at Runnymede Collegiate Institute in Toronto where he was elected President of the Student Council in 1973.

He campaigned as a Liberal for a 1982 provincial by-election in York South, but lost to new NDP leader Bob Rae.

He was chairman of the Canada-Taiwan Parliamentary Friendship Group and headed a Caucus Task Force on Pearson International Airport.

[8] Nunziata introduced several Private Members Bills including those to repeal the Faint Hope Clause of the Criminal Code of Canada and to modify the Young Offenders Act.

[9] In the buildup to the 1993 federal election, Nunziata criticised Liberal leader Jean Chrétien for appointing Art Eggleton over a local candidate in York Centre.

He defeated Toronto councillor Judy Sgro by 4,431 votes to retain his riding, and so became the only independent member elected to the new parliament.

[11] Nunziata started his political career in 1978 when he was elected an alderman in the former borough of York at age 23 and while still attending law school.

[12] He ran for Mayor of Toronto in the 2003 municipal election, pledging support for the police, and to bring the homeless off the streets and into institutional care facilities.

[16] On September 12, 2014, the last day to register as a candidate, Nunziata registered to run for Toronto city council in Ward 12 (York-South Weston) against incumbent Frank Di Giorgio, community leader Lekan Olawoye and former city staffer Nick Dominelli in the October 27 municipal election.