"This is a government that is speaking out of both sides of their mouth," said Robyn Benson, head of the Public Service Alliance of Canada.
"You can't on one hand say, 'Oh, we want to negotiate fairly,' but on the other hand say, 'We're really, after X amount of time, going to take away your sick leave.'"
The government wants to get rid of the system whereby public service employees can bank sick days and instead provide short-term disability benefits through an insurance company. Sick leave has been the subject of contentious contract negotiations for the past year.
On Tuesday, the 2015 federal budget said that negotiations held to date "reflect the government's commitment to good faith collective bargaining." But it also added that if negotiations fail, it will "take the steps required to implement the changes within a reasonable timeframe."
The government said the overhaul will clear $900 million in future liability to sick leave, which it is applying to the coming fiscal year to help the reach a $1.4-billion surplus.
Sahir Khan, economist and visiting fellow at University of Ottawa, said that the government's plan to change the sick leave program is "one of the largest contributors" to achieve the surplus.
Debi Daviau, head of the Professional Institute of the Public Service, said members are still feeling the sting of previous budgets.
"With an operational budget freeze still in play from last year, and over $14 billion in cuts still going through the system, the cuts have not ceased," she said. "By the end of this year, we expect to have lost 7,500 scientific and research positions."
Union leaders plan to return to their members to figure out how to best defend their bargaining rights.
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