Stewart has served his community in the provincial government as MLA for Coquitlam-Maillardville from 2001 to 2005;[3] appointed MLA Responsible for Francophone Affairs,[5] member of the Government Caucus Committee on the Economy, and Chair of the Select Standing Committee on Education.

Stewart was previously President of the Canadian Home Builders' Association of British Columbia, Chair of the National Housing Economic Research Council, a member of the BC Minister's Advisory Council on Affordable Housing, a member of National and BC Building Code Committees, and a member of the National Research Council Canada's Standing Committee on Housing.

In 2004, MLA Elayne Brenzinger, then an independent, accused Stewart of improper conduct, claiming he had groped her.

[9] In 2016, Stewart revealed that he had been wearing the same suit to work events for the past fifteen months, in an effort to highlight the double standard that women in the public sphere, particularly in politics, are subject to over their appearance.

[13] In fall 2022, a lawsuit filed by Metro Vancouver alleged that Anika Calder, the daughter of Coquitlam city manager Peter Steblin and an employee with Acciona, had used Stewart's login and password access confidential legal documents relating to this dispute, then provided copies of the documents to Acciona.