The vote marked a milestone for the province's national assembly: the Canadian flag has never before remained on official display in the building when the pro-independence PQ has held office.
Members of the sovereigntist party erupted in jeers and sarcastic cheers as their motion to remove the flag went down to defeat.
The target of their heckling was the province's newest political party. The Coalition Avenir Quebec is led by a staunch former Pequiste, Francois Legault, but the new party has always positioned itself as neutral on the independence question.
Now the PQ says that the flag vote has illustrated, once and for all, how that neutrality is a sham. It says the Coalition's sympathies have become clear.
The motion sponsor said there are now two pro-Canada parties in the legislature, the Liberals and Coalition, and independence-minded voters will have to think twice before backing either of them.
"I saw them stand up, one by one, and I hope that voters in their often-nationalist and often-sovereigntist ridings saw them stand up and support an ultra-federalist position," Yves-Francois Blanchet said of the Coalition members.
"It is a sombre and mildly shameful action."
Blanchet called it an affront to tradition, to protocol, to dignity, and to the notion that Quebec's parliament "belongs only to us." He described the vote as a step backward.
In fact, it was a bittersweet day for Blanchet: he also happened to have been named the province's environment minister earlier Tuesday.
His motion demanded that the flag be removed during parliamentary work in the old upper chamber, the only place in the legislature where the Maple Leaf is on official display.
Although the so-called Red Room lost its original function decades ago when the Senate-like chamber was abolished, it is still regularly used by legislative committees and at formal events like cabinet swearing-in ceremonies.
The motion was defeated 65-33. The Liberals and Coalition outnumbered the PQ and the left-wing, pro-independence Quebec solidaire.
The flag has never stood in the legislature in either of the previous two eras that the PQ held office — and the issue had not generated comparable controversy in the past.
But this time the PQ's intentions prompted a backlash, with the party receiving criticism in social media and the news media.
The party has never governed with a minority before and, in this case, it was forced to seek the consent of other parties to remove the flag.
While all parties in the assembly have a clear stance on nationhood — for or against Quebec independence — the dispute placed the Coalition in a uniquely awkward spot.
Legault explained why he voted with the status quo.
"The CAQ is a coalition of sovereigntists and federalists. There are federalists who believe very much in Canada and I believe this (flag issue) is really not a priority," Legault said.
"Everyone will agree that with these reports of corruption, mismanagement, economic problems, this is not the time to be preoccupied with flags."
The vote came a week or so after an online poll asked respondents whether they considered different national symbols very important, somewhat important, not very important, or not important at all as sources of personal or collective pride in Canada.
The survey said that when it came to the flag, 66 per cent of Quebec respondents answered yes — with 29 per cent calling it very important and 37 per cent calling it somewhat important.
It was at the swearing-in of the new PQ cabinet several weeks ago that people noticed the flag had been removed.
The Canadian flag has had an on-again, off-again presence in the Red Room. It is the only visible spot in the building where the emblem hangs.
Marois' government made a formal request to remove it last month, on the 36th anniversary of the election of the first PQ government in 1976.
That year, then-PQ premier Rene Levesque was the first to put the Quebec flag in the legislative chamber, the Blue Room, where the daily debates are held and votes are cast. In 1983, he put the Fleur-de-lis in the Red Room.
The Maple Leaf was eventually added to the Red Room by federalist Liberal premier Robert Bourassa when he returned to power in 1985. It was removed by successive PQ premiers before being brought back in 2003 after Jean Charest's Liberals took power.
Neither federalist premier, Bourassa or Charest, put the Maple Leaf in the legislative chamber, fearing a backlash from nationalists.
-With files by Martin Ouellet in Quebec City and Alexander Panetta in Montreal
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