The Public Service Alliance of Canada walked away from bargaining meetings that were scheduled for this week after the government introduced proposed changes to sick leave as part of its budget implementation bill.
Bill C-59, introduced Thursday, would give the government the ability to unilaterally create a new short-term and long-term disability program.
Proposed changes to the sick leave provided to federal civil servants are among the most contentious issues at stake in contract talks with public service unions, including PSAC.
If the budget implementation bill in its current form becomes law before Parliament rises for the summer, the federal Treasury Board Secretariat will have the power to establish and modify the "terms and conditions of employment related to the sick leave of employees."
That goes against the Charter of Rights and Freedoms, and the union will use every legal means necessary to oppose the provision, said Robyn Benson, the union's national president.
"One just needs to look at Division 20 (of the budget implementation act), where they're going to take away our collective bargaining rights," said Benson.
"It's against the charter and, certainly for us, it's just wrong, what they're doing."
Treasury Board President Tony Clement has said on numerous occasions the Harper government wants to continue bargaining for a new collective agreement, and called Monday's move by the union "very unfortunate."
"I have made concessions to them at the bargaining table, which they have not responded to, so they have been very obstructionist," Clement said outside the Commons.
The April 21 budget included savings of $900 million in the current fiscal year that the government expects to generate through the negotiating process.
Clement has suggested that number is a soft target, but Employment Minister Pierre Poilievre, who represents an Ottawa-area riding where many federal civil servants live, has insisted the savings budgeted by the government are "set in stone."
Failing to reach that target would remove a large chunk from Finance Minister Joe Oliver's projected $1.4-billion budget surplus for 2015-16.
The Conservatives have maintained that current sick leave provisions have created a huge liability on the government's books because of the amount of sick time that civil servants have accumulated over the years.
But the union maintains that the liability doesn't exist.
Clement has also called the sick leave system unfair to many government employees.
"We have a system in place now where if you are seriously ill, for two-thirds of the employees who get a serious illness, there’s not enough sick time for them," he said.
"And yet other people have a lot of banked sick days. So we want a system that’s fair to everybody, including the taxpayer.
Benson said the union will re-evaluate whether to continue bargaining after consulting with its members and other unions in the coming days.
Delegates at a PSAC convention last month unanimously passed an emergency resolution setting aside up to $5 million for a campaign to oppose government actions that diminish members' rights.
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