A letter sent to each of the five political parties asks for a platform commitment to modernizing the existing regime governing charitable groups.
Without it, there's the risk of losing what the civil society sector can contribute to the broader public good, says the letter, signed by environment, public policy and international aid organizations.
"The work of charities contributes greatly to Canada’s democracy and the health and vigour of our democracy depends on much more than citizens voting in elections," the letter said.
"The extent to which elections are informed and motivated by citizens engaging with each other on issues they care about is an indicator of the overall health of our political system."
But charities are now fearful of carrying out that work thanks to the ongoing crackdown by Canada Revenue Agency, the letter said.
Since 2012, CRA has been auditing charities to look for those spending more than the legal 10 per cent of their time and resources on political activity.
But there are broad interpretations of what that means and to what extent groups can engage in the policy development process, the letter said.
"The result is a chill, where charities feel that their efforts are being discouraged, subjected to rhetorical attacks or harsh or arbitrary review," the letter says.
The audits have targeted organizations ranging from a local bird watching group to the major Canadian Centre for Policy Alternatives.
"The whole sector is a big mess and it's time the parties — whoever forms the next government — they need to really bear down on this question," said Bruce Campbell, the executive director of the centre, among those who signed the letter.
Claims that the audit process is biased have been repeatedly denied by the Canada Revenue Agency, which says its choices of audit target are based on criteria that have nothing to do with partisanship.
A spokesperson for the revenue minister wouldn't say whether the minister would support clarifying the law.
"The department, and the department alone, is responsible for interpreting the rules laid out in the Income Tax Act as they pertain to charities," Carter Mann wrote in an e-mail.
To some extent, the current atmosphere will change what charities talk about in the election campaign, said Eric Hebert-Daly, the executive director of the Canadian Parks and Wilderness Society, which also signed the letter.
They hope supporters will raise the cause of changes to the tax regime as well as other issues when politicians come knocking, he said.
"We continue to believe strongly that no charity should be involved in any kind of partisan activity at any level, that that is a line that should never be crossed," he said.
"But this involvement in public policy issues is really way too open to interpretation for any kind of sanity around it."
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