Denis Lemelin, president of the Canadian Union of Postal Workers, said the relatively new sick leave system at Canada Post hasn't worked out for his members or the workplace.
"It changed a lot of things," said Lemelin. "It's the fact that it's personal days and what is happening is people are coming to work sick, so that's the reality."
Canada Post negotiated a new sick leave policy that was implemented in 2013 after a labour dispute, during which sick leave was one of the key issues.
CUPW members went from being allowed 15 sick days a year to the current system of five personal days, Lemelin said.
Once those five days are used up, postal workers must then apply to an insurance company for short term disability.
Sick leave big issue in current negotiations
Right now, the federal government and public sector unions are at odds over a new sick leave policy for public sector workers. In last week's budget, the government said it could save more than $1 billion by scrapping the current sick leave regime.
But public sector unions have vowed to fight the cut.
Robyn Benson, president of the union representing the largest number of federal workers, the Public Service Alliance of Canada, said the Canada Post example is a cautionary tale for her members.
"At Canada Post for example, they get X amount of days … but if you don't have those you go on leave without pay," said Benson. "It's certainly not management now trying to ensure that their employees are healthy. This is an insurance company saying, oh, you must come back to work. I think, on so many levels, it's just wrong."
The insurance company that runs the short-term disability program for Canada Post is Morneau Shepell. When the federal government initially announced it would revamp the sick leave system, Morneau Shepell sent out a media release praising the initiative.
"We applaud the Government of Canada for taking a much-needed step to modernize its human resources practices," stated the news release from June 2013.
'I'm here for the public servant who wants to work hard ...,' Treasury Board president says
Officials at the Treasury Board would not say how much a public service new sick leave system will cost to implement.
"I'm here for the public servant who wants to work hard, who needs sick benefits when they are truly sick … but I'm also for accountability ... on behalf of the taxpayer," said Treasury Board President Tony Clement last Wednesday in a scrum with the press.
Canada Post said its revamped sick leave plan was "part of a long-term strategic initiative to align costs with our competitors" and was drawn from industry best practices.
But officials there would not say if any savings have been realized.
"This information is commercially sensitive and therefore not public," Canada Post stated in a note to CBC News.