The man who could be the next leader of Canada once called another member of parliament a 'piece of s---'

Election season is underway in Canada, where an Oct. 19 vote will determine who will become the next prime minister.

A lot of eyes are on Justin Trudeau, the leader of the Liberal Party, and the son of former prime minister Pierre Trudeau.

A school teacher by trade, Trudeau Jr. has been on the political scene for a while, although he only became leader of the Liberal party in 2013. For 5 years before that, he was a member of parliament, representing part of Montreal.

Trudeau is young, attractive, and charismatic. But the Conservative Party, under current-PM Stephen Harper, has used his boyish looks and relative inexperience against him, launching a hugely successful attack ad that claims "He's just not ready."

(The ad also makes a crack at Trudeau's signature shaggy hairdo, although these days he's wearing a tighter crop.)

But in some ways, Trudeau has made it easy for his opponents.

Call it immaturity or call it passion, Trudeau has made some questionable decisions as a politician - from dropping an F-bomb at a charity event to the time he made a penis joke about dropping actual bombs on ISIS.

Perhaps the most memorable incident, though, was back in 2011, when in a heated parliamentary debate about the Kyoto Protocol, the young Trudeau called the environment minister, Peter Kent, a "piece of s---."

He didn't just say it. He shouted it. You can watch it here (about 15 seconds in):

 Trudeau apologized for the incident immediately after the question period.