Marcoux was a Parti Québécois member of the National Assembly of Quebec from 1976 to 1985 and was a cabinet minister in the governments of René Lévesque and Pierre-Marc Johnson.
"[3] He later announced that Lévesque government would tax the tips earned by waiters and waitresses via a weekly paycheque reduction; this proved to be an unpopular measure and was never enacted.
[5] His national assembly biography indicates that he ceased to be the public works minister on October 1, 1984, although newspaper reports from 1985 suggest that he still held the position in a later period.
[7] Shortly after his appointment, Marcoux concluded what had previously been a contentious dispute with the government of Canada over job-creation grants to municipalities.
[9] Later in the same year, Marcoux announced seven hundred thousand dollars in funding to help move failing day-care centres into public buildings.
[10] In May 1985, he and transport minister Guy Tardif introduced legislation to allow Montreal and South Shore residents to have public meetings on the state of municipal transit.
[11] Marcoux also introduced legislation to restrict the amount of money that municipal political parties could raise from anonymous sources.
He was the director of intergovernmental relations for the Union des Municipalités du Québec from 1989 to 1991 and served as director-general of Sainte-Foy, Quebec from 1991 to 2001.