He was the Member of National Assembly of Quebec for the riding of Jonquière in the city of Saguenay from 2007 to 2022.

He also received a bachelor's degree in law at Université Laval and was admitted to the Barreau du Québec in 1996.

He had faced controversy during the campaign, when radio host Louis Champagne attacked both Gaudreault and Parti Québécois leader André Boisclair for being openly gay.

While his stint in Cabinet only last 19 months due to the PQ's defeat in the subsequent election, he announced plans to extend the Montreal Metro's Blue Line to Anjou and the Yellow Line deeper into the Monteregie.

As well, he became the point person on the government's plans to further electrify public transit across Quebec.