In 1872, he served as parliamentary correspondent in the provincial assembly for Le Canadien.
In 1873, he became a member of the town council in Trois-Rivières and served as mayor from July 1876 to July 1877.
Turcotte was elected to the Legislative Assembly of Quebec for Trois-Rivières in an 1876 by-election as an independent Conservative; he was reelected in 1878.
Turcotte served as speaker of the assembly from 1878 to 1882.
He was named Queen's Counsel in 1878.
In 1879, he helped found La Concorde, becoming its editor.
He was defeated in 1881, now running as a Liberal but, after his opponent was unseated because he was accused of bribery, won the seat in an 1884 by-election; he was reelected in 1886.