Justin Trudeau is worried about extremism entering Canada through the electoral system.

If like Canada, France had a first-past-the-post electoral system, Marine Le Pen of the extreme-right National Front would be well placed to be the next president of France. She has led the polls for months.

Instead, because France has two rounds of voting, with the second round limited to the top two finishers in the first round, Le Pen has next to no chance of winning (regardless if she finishes first or second in the first round).