Born in Edmonton, Alberta, Duncan moved to Whitehorse, Yukon in 1964. She
completed her Bachelor of Arts in political science at the University of Ottawa.
Duncan was leader of the Yukon Liberal Party from 1998 to 2005, she was MLA for Porter Creek South
from 1996-2006. Duncan led her party into a majority government in 2000, she was the second female
political party leader in Canadian history to do so. In 2005, Duncan was defeated as leader of the Liberal
Party by Arthur Mitchell, by a margin of 54 votes. Duncan did not seek re-election in 2006.