Career
On December 11, 2003, following Paul Martin"s election as leader of the governing Liberal Party of Canada and the day before Martin"s swearing in as Prime Minister, Lanctôt crossed the floor to join the Liberals. His defection occurred days after his riding association passed a resolution stating it no longer wished to work with the Member of Parliament and did not want him to run for the BQ in the next election. Lanctôt ran as a Liberal in Châteauguay—Saint-Constant in the 2004 federal election but was defeated by the BQ"s Denise Poirier-Rivard.