The tables turned Tuesday after the Barrie Advance newspaper outed the PMO as the source of documents circulated to media Monday showing three fundraising events headlined by Trudeau in 2006 and 2007 — before he became an MP — lost money.
The prime minister's staff were also busy last week handing out copies of a letter from the Grace Foundation, a New Brunswick charity that wanted Trudeau to reimburse his $20,000 fee for speaking at a money-losing event last year.
It has since been revealed that at least one member of the foundation's board is a well-connected Conservative, whose husband is on the executive of local Tory MP Rob Moore's riding association.
Questions about the propriety of using his taxpayer-funded office to launch strictly partisan attacks followed Prime Minister Stephen Harper all the way to Northern Ireland, where he held a wrap-up news conference Tuesday at the end of a G8 summit meeting.
Harper gave a somewhat rambling response which did not address the issue.
"Look, my view is, in terms of my own comportment, my view is that what is not appropriate, I, you know, as someone who is paid by the public, I get good remuneration from the taxpayers of Canada, as a public servant, I don't think it's appropriate for me to then take money from charities," he said.
"I give money to charity, I don't take money from charity. So that's my view on what's appropriate and not appropriate under those circumstances."
A spokesperson for Harper later added that the prime minister intends to donate the proceeds from his long-awaited book on the history of hockey to the Military Families Fund.
Back in Ottawa, however, critics weren't so reticent about addressing the issue.
"I see that as a very inappropriate use of taxpayers' funds," said Edmonton MP Brent Rathgeber, who quit the Conservative caucus last month in frustration in part over PMO muzzling and/or scripting of backbenchers.
Rathgeber likened the latest PMO-orchestrated attacks on Trudeau to the anti-Trudeau flyers that Tory MPs were encouraged in April to send out to their constituents — at taxpayers' expense.
"If the party mechanism, you know, wants to come up with those types of products or engage in that type of purely partisan warfare, that should come from the party machinery, not from the taxpayers-funded PMO."
He attributed the problem to the "young, really aggressive, really motivated, hyper-partisan" staffers in the PMO who believe "digging up dirt" on Trudeau is part of their job.
NDP ethics critic Charlie Angus chided Harper for allowing controversy over Trudeau's "ethical misjudgment" to be turned into an issue about his own judgment.
"The issue I think that Canadians have to ask themselves (is): Doesn't the prime minister have more important things to do in terms of serving our country than running a black ops operation against the Liberal leader?" Angus said.
"It's not becoming of the prime minister."
Angus said the Tories are blowing the political gift Trudeau handed his rivals when he chose to voluntarily disclose that he's earned $277,000 making speeches to 17 different groups since becoming an MP in 2008.
"It was gift-wrapped for you ... and just out of sheer stupidity, block-headedness and spite, you're blowing it," he said.
Trudeau announced Sunday that he will speak to all 17 groups and return the fees to any group that feels it didn't get its money's worth.
However, Harper's office made no apologies for its role in fanning the flames of the controversy.
"News flash: the office of the leader of the Opposition, the Liberal leader's office and the Prime Minister's Office all engage in political communications," said PMO spokesperson Julie Vaux in an email.
"Trudeau's taxpayer-paid staff are currently calling all the charities (about returning the speaking fees) and that's supposed to be his personal business."
Vaux said Trudeau only agreed to reimburse the Grace Foundation after the media pounced on the story and "our caucus shamed him into doing so."
Conservative MP Ben Lobb, meanwhile, told the House of Commons he intends to ask federal ethics watchdog Mary Dawson to investigate whether Trudeau broke conflict of interest rules by voting on a bill involving the rights of labour unions when he's accepted "over $100,000 in personal payments from unions."
Trudeau has said Dawson gave him the green light to continue his public speaking career after he was elected in 2008. According to the record of paid speaking engagements he's voluntarily disclosed, he's spoken to only one union, for a $20,000 fee, since he was elected,
The Conservatives maintain it was unethical of Trudeau to ever accept a fee for speaking to charitable organizations, either before or after becoming an MP. And they include municipalities, educational institutions, school boards and other non-profit entities in their definition of charity.
However, one of their own — former NHL coach Jacques Demers, whom Harper appointed to the Senate — admitted Tuesday that he too has accepted payment for speeches to literacy groups and others the Conservatives describe as charities.
"I've taken and I've given a lot," Demers said.
"All I want is the people who have hired me have got more than their money back because they use your name. If not, there probably won't be anybody in the room."
Demers added that he doesn't take money from charities, such as battered women's shelters, that have personal meaning to him.