[1] L'Allier was born in Hudson, Montérégie in 1938 and received a law degree from the University of Ottawa.

L'Allier was defeated against Parti Québécois (PQ) candidate Pierre de Bellefeuille in the 1976 election.

L'Allier ran as the Rassemblement populaire candidate for Mayor of Quebec City in 1989.

He won against Progrès civique de Québec candidate Jean-François Bertrand and was sworn in as the 38th Mayor of the city.

L'Allier co-founded the Renouveau municipal de Québec and was re-elected as mayor in 2001 against Action civique de Québec candidate and former anti-merger crusader Andrée Boucher.