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       Chris Aylward, Public Service Alliance president, says that discipline and termination to enforce a vaccine mandate are ‘totally unacceptable.’

       DAVID CHAN/The Globe and Mail

       Canada’s largest federal public sector union is pushing back against promises from party leaders that government employees who do not adhere to a mandatory vaccination policy could be disciplined, an issue that has dominated the first three days of the federal election campaign.

       The Public Service Alliance of Canada (PSAC), a union that represents more than 180,000 members nationally, said on Tuesday it supports vaccination requirements for federal workers to ensure safety in the workplace and the community.

       But Chris Aylward, the national president of PSAC, told The Globe and Mail on Tuesday that discipline and termination to enforce such a mandate are “totally unacceptable.” PSAC members have rights in the workplace including when it comes to disciplinary measures, he said.

       “We will take whatever action is necessary to defend our members around this issue,” Mr. Aylward said. “It is very concerning to see national party leaders call for workers to be disciplined or fired over the government’s vaccination requirements.”

       PSAC has been in discussions with the federal government on its vaccination proposal. On Tuesday, Liberal Leader Justin Trudeau said his party was unequivocal that civil servants must be vaccinated. “There will be consequences” for anyone who does not have a legitimate medical reason for not getting fully vaccinated, or chooses not to do so, he said in Markham, Ont.

       Earlier Tuesday, NDP Leader Jagmeet Singh said collective agreements must be followed for employees who refuse to be vaccinated without a reason related to health. The collective agreements include a process for progressive discipline, up to and including termination, he said.

       “Discipline should always be a last resort, but may be necessary in rare cases to protect the health and safety of Canadians,” Mr. Singh said.

       Mr. Aylward said it is very concerning to hear national party leaders say workers would be disciplined or fired over federal vaccination requirements.

       “We will take whatever action is necessary to defend our members around this issue,” he said.

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       Mr. Aylward also said it is not a coincidence the government announced mandatory vaccination for federal workers two days before Mr. Trudeau triggered the election on Sunday. The announcement on Friday included absolutely no mention of discipline, he said.

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       In addition to public servants, the announcement applied to federally regulated industries and travellers on domestic planes, buses, trains and cruise ships.

       On Tuesday, the Conservatives asked the interim clerk of the Privy Council for an “immediate investigation” into the removal on Monday of an online government memo that seemed to contradict the Liberals’ promise on mandatory vaccinations.

       In the memo to deputy ministers posted on Friday, Christine Donoghue, the Chief Human Resources Officer of Canada, said the government would consider alternatives for people who refuse vaccination, “such as testing and screening.”

       In a letter to interim clerk Janice Charette on Tuesday, Conservative MP and candidate Michael Barrett said the removal is a “serious breach” of guidelines known as the caretaker convention, which require a government to “act with restraint during an election period.”

       The Conservative Party is asking for a probe to identify all the individuals involved in the decision to remove the memo to determine if they were members of the bureaucracy or political staff and politicians. In his letter, Mr. Barrett asked that the investigation be conducted right away and that the findings be released before election day, Sept. 20.

       In their letter requesting an investigation, the Conservatives accused the government of asking the bureaucracy “to intervene for partisan political purposes” during an election campaign.

       While promoting his party’s $10-a-day child-care plan on Tuesday, Mr. Trudeau told reporters the memo was taken down because it was erroneous and did not reflect government policy, adding it was removed by the public service.

       He did not answer when asked directly whether his team had any role in the decision to take it down.

       The Conservatives said late Sunday that they would not implement a vaccination mandate, but would require unvaccinated civil servants to take daily COVID-19 rapid tests, and that air and train passengers would have to have rapid tests or proof of a recent negative test.

       Mr. Trudeau said the Liberal policy is not the same as that of the Conservatives.

       “It would be great if they had the same position as us. It would be good for Canadians if they did,” he said. “They won’t even say whether or not all their candidates are fully vaccinated in this election.”

       Conservative Leader Erin O’Toole accused Mr. Trudeau of a cover-up at a campaign stop in a hotel in Toronto on Tuesday, where he promoted his proposal to suspend the GST for purchases in retail stores this December at a cost of $1.5-billion.

       “Mr. Trudeau needs to come clean with whether the plan that was on the website before he covered it up is actually their plan,” Mr. O’Toole said.

       He said vaccines are a critical tool, but sometimes testing and masking may be useful in dealing with COVID-19.

       “We need to bring people together, not divide,” he said.

       Some experts are concerned that a split along party lines on the matter could affect attitudes toward vaccination. “When it becomes more of an ideological belief, we run into trouble,” said Kumanan Wilson, a professor at the University of Ottawa who’s studied anti-vaccination sentiments.

       Dr. Wilson said the Liberals and Conservatives are “definitely polarized” on this issue, and even though both parties generally support vaccination, they’re framing it in different ways. He said he’s concerned some people won’t get vaccinated because of this and put themselves and those around them at risk.

       In Montmagny, Que., east of Quebec City, Bloc Québécois Leader Yves-Fran？ois Blanchet said Mr. Trudeau’s vaccination policy appears to be voluntary and not mandatory.

       “It isn’t clear what he is saying here.”

       With reports from Laura Stone, Menaka Raman-Wilms, Bill Curry and Robert Fife in Ottawa

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