Harper unveiled the measure in Sherbrooke, Que., in the company of parents whose children were the victims of some of the most high-profile, and grisly, killings in recent Quebec history.
They included Bruno Serre, whose 17-year-old daughter Brigitte was brutally slain while working the night shift at a Montreal gas station in 2006. Serre returned to his job at a hardware store barely five weeks after his daughter's death.
"We had three children at home — they had to be able to eat," Serre said.
"They were in school... (but) one dropped out and fell into drugs. It's altogether normal because we weren't there to take care of them."
The income-support benefit announced Friday will provide families who lost a child during a crime with $350 per week, for a maximum of 35 weeks. But to qualify, parents will have to have made at least $6,500 in the previous year and be taking time off work.
An estimated 1,000 families will be eligible for the benefit, which comes into effect in 2013.
"What they live through is obviously a tragedy that completely changes their lives," Harper said.
"This financial help won't be able to give them justice, nevertheless it will contribute to giving a chance to parents of victims to retake their lives in hand."
Along with the supplement, Harper also promised to seek changes to the Canadian Labour Code that would allow certain workers to keep their jobs while taking time off to cope.
Harper cast the added help to victims in the context of his government's so-called tough-on-crime approach, saying it was part of a broader effort to strike a new balance between the rights of victims and those of criminals.
Taken together with the elimination of the faint-hope parole clause and the imposition of mandatory minimum sentences for sex offenders, the new measures indicate Ottawa is listening to victims, Harper said.
"Too often, victims have the impression that it is criminals who have all the rights," he said. "The pain of victims is amplified by a feeling of injustice and the impression of being abandoned by the justice system.
"We are committed to once again making the victim the central focus of the criminal justice system," he added.
Harper was joined by Sen. Pierre-Hugues Boisvenu and members of the Murdered or Missing Persons' Families' Association. Boisvenu founded the association after his daughter Julie was murdered in 2002.
Since being named to the Senate in 2010, Boisvenu has become a key spokesperson in Quebec for the Conservative government's crime polices, many of which are controversial in the province.
Boisvenu praised Harper for leading the "first government dedicated to the defence of the rights of victims, and to put those ahead of criminals." That sentiment was shared by members of the association present for the announcement.
"We always hear about his bad moves, but I think this time we really (have to) tell everyone that... he is the first prime minister... to listen to the victim," said Isabelle Gaston.
Gaston was dragged into headlines in 2009 after her ex-husband stabbed their two children to death, in a case that angered Quebecers. Her husband, Guy Turcotte, was found not legally responsible and is now applying to be released from a psychiatric institute.
Gaston has led a crusade to increase the financial compensation that crime victims receive from governments. Her efforts resulted in the Quebec government recently boosting its victim fund by $500,000.
"When you lose a child, you're losing part of yourself," she said.
"You feel like you lack oxygen, like the sun won't be bright again. The thing that you need is stability. You need to take time to breathe."
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