Simard was 67.
The ultra-nationalist FLQ arose in the 1960s, and was connected to a string of bombings that were sometimes indiscriminate and often directed at government buildings.
The escalation of the campaign involved the kidnappings, by separate cells of the group, of British trade commissioner James Cross and Quebec Labour Minister Pierre Laporte over a five-day span in early October 1970.
Prime Minister Pierre Trudeau invoked the War Measures Act on Oct. 16, giving the police powers to search and arrest without warrant. Troops and military vehicles became a commonplace sight, and hundreds were detained.
The controversial measure led to the famous "just watch me" comment from Trudeau, when asked by CBC reporter Tim Ralfe how far he would go with respect to civil liberties while trying to ensure public safety.
On Oct. 17, the 49-year-old Laporte's body was found in the trunk of a car. He had been strangled.
Simard conducted own defence
Cross was released in early December in a resolution that saw several FLQ members allowed passage to Cuba, although many were arrested in subsequent years when they returned to Canada.
The 23-year-old Simard, and Paul and Jacques Rose were captured in a rural area of Saint-Luc, Que., on Dec. 28.
The three, along with Bernard Lortie, were charged with the murder in the kidnapping of Laporte the following week.
When asked his plea, Simard replied, "I don't plead anything at all," according to a Globe and Mail report from court in Montreal.
Simard conducted his own defence at the trial, and received a life sentence for murder in May 1971. He was released on parole in 1982, and went on to write several books about the FLQ and the crisis.
He and the other three men charged with Laporte's murder were all paroled between 1978 and 1982.
Simard told the Montreal magazine Le Temps Fou in 1982 that Laporte was killed after the group no longer had the funds to keep him hostage.
Around the same time, he told a news conference to promote his book, Pour en finir avec Octobre, that they had not planned to kill Laporte when they originally kidnapped him.
But he rejected the notion that it was an accidental death, calling it a "sincere gesture to show that what we were saying was not just words," when the government wouldn't negotiate.
Simard refused to say which of the four strangled the minister.
Paul Rose died of a stroke in 2013.
Simard`s funeral will be held in Longueuil, Que., on Jan. 24.
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