He was born in Quebec City, the son of Honoré-Julien Chouinard and Marie Elisabeth Célina Pelletier. Chouinard was educated at the Collège Sainte-Anne, the Séminaire de Québec and the Université Laval. He was called to the Quebec bar in 1873. In 1884, he married Marie Louise Isabelle Juchereau Duchesnay, the daughter of seigneurElzéar-Henri Juchereau Duchesnay. He served as a member of the council for Quebec City. Chouinard was one of the founders of the newspaper La Justice. He was vice-president of the Quebec and Lac Saint-Jean Railway. Chouinard was also president of Le Club Cartier de Québec, the Quebec Geographical Society, L'Institut Canadien de Québec and La Societé Saint-Jean-Baptiste de Québec. He ran unsuccessfully in the federal riding of L'Islet in 1882. Chouinard was elected to the House of Commons in an 1888 by-election held after the death of his brother-in-law Henri-Jules Juchereau Duchesnay.
He served as clerk for the city of Quebec from 1890 to 1927. Chouinard published a number of works including Histoire de la Societé Saint-Jean-Baptiste de Québec.[1] He was one of the first to advocate a major celebration for the tricentennial of Quebec City in 1908 and the establishment of a park on the Plains of Abraham.[2] He was appointed Companion of the Order of St Michael and St George in 1908 as the Secretary to the National Battlefields Commission, Quebec.