A tentative agreement reached between the Trudeau government and Canada's scientists would lock in their right to speak to the media about science and their work for another four years.

The "scientific integrity" clause was first written into a 2017 collective agreement and enshrined the right to speak about science and their research without being designated a departmental spokesperson.

The Liberals, under Prime Minister Justin Trudeau, agreed to renew the clause at the June 7 conclusion of bargaining for a contract that would replace the one that expired last fall for most of the three groups included — researchers, scientists and engineers.

The right to speak would survive even if the Liberals are defeated in the October federal election, if the tentative contract is ratified.

The contract affects about 15,000 scientists, researchers and engineers across the country, about 1,000 of them in Atlantic Canada.

"It was one of the most important things we've ever done," Debi Daviau, president of the Professional Institute of the Public Service of Canada (PIPSC) union, said about renewing the scientific integrity clause.

Debi Daviau, national president of the Professional Institute of the Public Service of Canada union, says preserving the right for federal scientists to speak to the media on science is important. (Robyn Miller/CBC)

Daviau said the union is well aware the Liberals could be replaced by the Conservatives, who were accused of muzzling scientists when they were last in power.

"It was the one that was most important to get into our collective agreement because now they're going to pry it from my cold dead fingers to get it back," she said.

The Harper government imposed speaking restrictions on scientists, including a requirement to get their talking points approved by Ottawa.

Protesters dressed as an MP, a librarian and a scientist wear gags during a demonstration against the muzzling of federal scientists in 2013 under the previous Conservative government. (Chris Wattie/Reuters)

Daviau said that in Opposition, the Conservatives "seem to have a slightly different stance," but she is skeptical.

"All the evidence points to a Conservative government that denies climate change, that doesn't believe in scientific facts and evidence, particularly if they're inconvenient and for sure, we're deeply worried," she said.

"If there is a government change, you can bet that we'll be spending a lot of our time trying to educate a new government on these priorities."

Conservative Leader Andrew Scheer's office did not respond to a CBC News inquiry about the party's position on scientists speaking to the media.

What the Liberals have done for scientists

Beyond allowing scientists to be more accessible to reporters — you can actually call them up — the Liberals have taken a number of measures to restore the independence of scientists in the federal public sector.

They reinstated the position of chief science officer, and have implemented policies and guidelines inside departments to ensure "all scientific research, products and their communication are free from political, commercial and stakeholder interference."

Those would be easier to eliminate by a new government, Daviau said.

Some scientists still feel muzzled

Last year, PIPSC released the results from a poll that looked at whether federal scientists feel they can speak freely. More than half of the respondents said they couldn't.

It was an improvement from the results of a similar poll in 2013 under Harper's Conservative government, when 90 per cent of respondents said they were not allowed to speak freely to the media.

However, the response rate wasn't very high in both surveys. It was 26 per cent in 2013 and 19 per cent in 2017.

The tentative agreement reached this month is being presented to all union members for a ratification vote. Because three groups are being represented by the union, voting will take some time, between mid-July and mid-August, says Johanne Fillion, communications officer for the PIPSC.

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