Chris Wattie / Reuters Former Employment and Social Development Minister Pierre Poilievre speaks during Question Period in the House of Commons in Ottawa on Feb. 16, 2015.

At the time, Poilievre — the social development minister — said the payments were from "our Conservative government," adding that "if the Liberals and NDP were to take office they would take the benefits away and raise taxes."

Poilievre wore the blue shirt with the large "C" at two announcements on the same day about an increase in the value of the now defunct universal child care benefit.

Canada's election watchdog said Friday that the former Conservative cabinet minister's decision in 2015 to wear a party-branded shirt to announce an expansion of child benefit payments broke election financing rules.

OTTAWA — If he had to do it all over again, Pierre Poilievre would have worn a suit.

In a ruling published Friday, the commissioner of Canada elections says Poilievre's choice of leisure wear coupled with his statements made the occasion more like a campaign event.

This made the approximately $4,800 in spending related to the events, which the government picked up, "a de facto non-monetary contribution" to the Conservative party, and afoul of election rules that limit political donations to citizens or permanent residents.

"The government of Canada is not eligible to make such contribution to the party," the notice says.

Poilievre had faced criticism for his shirt during the July 2015 announcement marking the arrival of 3.8 million payments valued at almost $3 billion to families with children age 17 and under. The payments were a result in an increase in the value of the benefit, and an increase in the number of children eligible.

"The government of Canada is not eligible to make such contribution to the party."

The Liberals and NDP at the time saw the announcement made in the dead of summer, and three months before election day 2015, as a ploy to buy votes.

The commissioner notes that Poilievre talked in waxing terms about the expansion to the payments, referring to them as "the biggest single one-time pay out in history" and "Christmas in July" for Canadian parents.

But it was the shirt that caught most people's attention — even one of Poilievre's staffers.

The commissioner's notice, known as a compliance agreement, says that one of Poilievre's ministerial staff questioned his fashion choice shortly before the Halifax announcement. Poilievre confirmed that he wanted to wear that shirt.

"In retrospect, he would have worn a suit"

In the ruling, the commissioner notes Poilievre told him: "in retrospect, he would have worn a suit."

The text of the compliance agreement says that Poilievre's intention was to link the child care benefit to the party, "and to provoke the media to cover (Conservative party) involvement in the funding."

The commissioner says that Poilievre's words and clothing were designed to make a "positive association" between the party and the benefit to curry gain a partisan advantage in the ensuing election.

In doing so, the commissioner said, Poilievre broke election financing rules and he's ordered the now-opposition MP to post a link to the ruling on his website, his Facebook page and his Twitter account.

Poilievre agreed to comply with the relevant provisions of federal election financing laws in the future.

He has not responded to a request for comment.

The notice was posted at the end of a week where Prime Minister Justin Trudeau toured the country to promote his government's child benefit, which replaced the universal child care benefit and two tax measures. Speaking in Shelburne, N.S. on Friday, Trudeau wore a blue shirt.

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