At issue is a $600,000 grant to her family's charitable foundation.
It was a donation for youth employment programs in Colombia and it didn't cause any controversy last year when it was announced by Canada's Department of Foreign Affairs, Trade and Development as a contribution to the Bill, Hillary & Chelsea Clinton Foundation.
But it's found new life in an American political story.
An early knock against Clinton's still-unannounced presidential bid is the notion that she'll be in a quasi-permanent state of conflict of interest, thanks to the almost US$2 billion pumped into the family foundation by deep-pocketed philanthropists around the world — many of whom have business concerns before the U.S. government.
This week, U.S. media started noting all the donations by foreign governments — which had been mostly suspended while she was secretary of state but have resumed since she left government.
That's where the Canadian donation comes in.
The Wall Street Journal pointed out cash from the United Arab Emirates, Saudi Arabia, Oman, Australia, Germany and a certain Canadian "government agency promoting the Keystone XL pipeline." Clinton had previously worked on the Keystone file as Secretary of State, and could oversee it in the future if she becomes president.
Other news reports led specifically with the Canadian angle.
One example was the congressional newspaper, the Hill. Its story began: "A Canadian government agency promoting the proposed Keystone XL oil pipeline donated hundreds of thousands of dollars to Bill and Hillary Clinton's nonprofit."
Clinton's opponents pummeled her with conflict-of-interest attacks when she initially ran in 2008 — and that's without her even making it out of the primaries to face the Republicans.
In anticipation that she'll become the nominee this time, the other party is already levelling the attack against her. A Republican political action committee, America Rising, called on her to return donations from foreign governments.
"The potential conflict of interest for someone in Clinton’s position requires they return the money," said the anti-Clinton group. "And the ethical lapse to accept the money in the first place calls into question Hillary Clinton’s judgment."
A conservative columnist in the Washington Post was scathing: "How will the American people ever be satisfied we are getting her undivided loyalty?" wrote Jennifer Rubin.
"Hillary, give the money back. Or don't run. You can’t keep the money and run."
Energy was one of five major priorities spelled out in a 2014-15 planning document for Canada's Department of Foreign Affairs, which sets out key objectives for the department and its $245 million budget.
The priorities listed in the latest Report on Plans and Priorities were: diversifying trade, promoting democracy and human rights, maternal health, alleviating poverty, and promoting Canada as a reliable energy source. In the 67-page document, there was one specific reference to Keystone.
The Clinton donation was announced in a press release last June 30. It was touted as part of a project to help more than 20,000 youths with job and education opportunities and 700 with internships in poor areas around Cartagena, Colombia.
The Canadian government objected to what it called false U.S. media characterizations of its contribution. The project was chosen through a Colombian call for proposals, it said.
"At no time in DFATD's preparation, review and approval of funding ... were Canada-U.S. bilateral issues such as the Keystone XL pipeline ever discussed or considered," said an email from department spokesman John Babcock.
"Any suggestions to the contrary are entirely without merit."
— With files from Bruce Cheadle in Ottawa
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