He represented the electoral district of Nelligan as a member of the Quebec Liberal Party.
Before entering politics, Coiteux taught economics and international business at HEC Montreal for 20 years.
While in office, he was made minister and a member of the Cabinet of Premier of Quebec Philippe Couillard.
[1] From 2014 to 2016 he served as President of the Treasury Board and since 2016 as Minister of Public Safety, Municipalities and responsible for Montreal.
On January 17, 2019, Coiteux was named as the Caisse de dépôt et placement du Québec's chief economist.