But tax returns filed to the Canada Revenue Agency show most of the foreign money that fills the coffers of Canadian charities does not go to the environmental groups now in Tory crosshairs.
An analysis by The Canadian Press of charities' 2010 tax returns found only one of the top 10 foreign-funded charities could be considered a conservation group.
That group is Ducks Unlimited Canada. Tax returns show it has reported receiving more than $33 million from foreign sources, making it the fifth-largest recipient that year of money from outside the country.
Ducks Unlimited Canada says it receives foreign funding from its sister organization in the United States, U.S. federal and state governments, corporations, private foundations and individual contributors.
Care Canada reported the largest amount of foreign funding in 2010. It accepted nearly $99 million from foreign donors.
Most of that money came from United Nations agencies, foreign governments and the charity's international members.
Second was World Vision Canada, which reported $89 million in foreign income.
World Vision Canada says the vast majority of that money comes from gift-in-kind donations from UN organizations and international corporations with branches in Canada.
"For example, these would be things like pharmaceuticals, clothing, school supplies and books and medical supplies," spokeswoman Tiffany Baggetta said in an email.
"Then we have a very small portion that is from individual citizens who just happen to live outside of Canada. For example, sometimes we have people who sponsor a child through World Vision Canada, then they move to another country but want to continue sponsoring that child through World Vision Canada."
Third was Hamilton's McMaster University, which, like many post-secondary institutions, has charitable status. McMaster reported $43 million in foreign income.
University spokesman Gord Arbeau says last year foreign students paid McMaster $25 million in tuition fees, while the school also received $13 million for research funding and $4 million from sales of medical isotopes from its nuclear reactor.
All that money counts as foreign funding for CRA's purposes.
The charity that reported the fourth-most foreign funding was the Canadian UNICEF Committee, with $37 million. But a UNICEF Canada spokeswoman says the organization doesn't actually receive much foreign funding.
"While it appears we received a significant amount of cash from foreign donors — we don't," Melanie Sharpe said in an email.
"That figure is almost entirely the value of donated health supplies that we send to our child survival programs in developing countries. Less than 0.5 per cent represents cash donations Canadians have made to one of UNICEF's global fundraising campaigns. ...
"According to accounting regulations all cash or in-kind donations have to be registered as revenue whether from a foreign or domestic source."
The CRA database shows only 1,998 of the 85,000 or so registered charities now active in Canada have reported any foreign income in 2010. Most are aid organizations, religious groups or schools.
All of their foreign funding in 2010 amounted to a combined total of $811,467,808. Since not every charity has filed its 2011 return, The Canadian Press only analyzed 2010 returns.
"It's certainly not as if this was something new," said Marcel Lauziere of Imagine Canada, an advocacy group for Canadian charities.
"And even if it were new, and it certainly is not, hard to understand why that would be a bad thing. I mean, unless Canada wants to isolate itself from the rest of the world, it would make no sense.
"You know, if 80 per cent of funding of charities came from foreign sources, you'd say, 'okay, that's a bit bizarre. What does that mean?' That's not the case at all. The lion's share, by far, of the funding that charities get are provided by Canadians."
Canadian charities do not have to disclose on their tax returns which foreign groups gave them money. But the recent federal budget promised to impose new penalties on charities that fail to provide full disclosure of funding and activities.
"There have also been calls for greater public transparency related to the political activities of charities, including the extent to which they may be funded by foreign sources," the budget document says.
Sanctions for charities that don't play by the rules could include fines or a suspension of a charity's ability to issue tax receipts.
Prime Minister Stephen Harper's Conservatives have been critical of charities that receive foreign funding, particularly environmental groups.
Natural Resources Minister Joe Oliver has accused "environmental and other radical groups" of trying to use money from "foreign special-interest groups" to hijack hearings on a pipeline that would bring Alberta oilsands bitumen to a port on the British Columbia coast.
Environment Minister Peter Kent even raised the spectre of criminal activity in a recent interview broadcast on CBC Radio's The House. Asked by host Evan Solomon if the government is trying to silence environmental groups by taking away their charitable status, Kent raised concerns about money laundering.
"Some groups with charitable status have been going well beyond the CRA guidelines for what is acceptable practice as a charitable agency," Kent said.
"And there has also been concern that some Canadian charitable agencies have been used to launder offshore foreign funds."
The minister was not available to speak to The Canadian Press.
One group that has been singled out for receiving American grants is Tides Canada, which runs both a grant-making foundation and a charity that backs environmental and social-justice projects.
Tides Canada reported $7.8 million in foreign income in 2010, according to its CRA tax return.
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