Liberal Leader Justin Trudeau should be praised, not pilloried, for taking part in the charity fundraiser that's now being featured in a Conservative attack ad, according to the event's auctioneer, a lifelong Conservative supporter.

Kent Browne, who told Ottawa Morning host Robyn Bresnahan that he was born and raised Conservative, said on the program Friday morning that he admires Trudeau for participating in the annual event, called What A Girl Wants. The Canadian Liver Foundation's event raises money and awareness about liver health for women.

Mostly women attend the dinner, which also features local Ottawa firefighters helping to serve the meal. A lunch date with Trudeau was one of the items up for auction. So was a backyard BBQ with the firefighters.

The Conservative television ad shows Trudeau taking off his shirt at the 2011 event while he walks up and down a runway. It asks viewers whether the Quebec MP has the judgment to be prime minister.

Browne isn't happy that the Conservative Party is using the footage against Trudeau in the ad campaign, which was launched immediately after Liberals chose him as their leader on April 14.

"He comes, and he's a great sport," Browne said. "So I admire that, and I think that's very hard to watch, (the Conservatives) take what was an in-fun, great event charity fundraiser in front of 400 women. If I looked like him, I'd be taking my shirt off too."

Browne said Trudeau is invited to hundreds of events a year, yet he has repeatedly chosen to support the Canadian Liver Foundation, and that should be applauded.

"I have no idea how great a prime minister he'll be or whether he's qualified," Browne said. "I just know he came out for a cause he believed in, for something that was important to friends of ours who have had a liver transplant, and it just seems to take the lustre off his having done such a great job.

Conservative Party stands by its ads

The charity auctioneer said he thinks using the footage against Trudeau could discourage politicians in the future from supporting causes and participating in a lighthearted way. He said he doesn't know if he will change his vote from Conservative to Liberal in the next election. That will depend on what Trudeau and the Liberals end up standing for when the time comes.

"All I can say is, he's one incredible guy," said Browne. He also wrote a letter to the editor that was published in the Ottawa Citizen saying that he was egging Trudeau on during the auction.

The Conservative Party stands by its use of Trudeau taking his shirt off at the event in its advertisements.

Judgment: To 'e' or not to 'e' Sharp-eyed readers may have noticed CBC.ca's spelling of judgment differs from that used by the Conservative Party in its ads and statements about Liberal Leader Justin Trudeau. The party spells it "judgement," while CBC (and Canadian Press) style is "judgment." What's the difference? While both spellings are acceptable, the Oxford English Dictionary prefers "judgement," whose first definition is "critical faculty, discernment," followed by "good sense," which are certainly the definitions the Conservatives are getting at. But the Canadian Oxford Dictionary goes with "judgment," which, Oxford also tells us, is the spelling "conventional in legal contexts, and in North American English."

"We believe Justin Trudeau's eagerness to perform a striptease, regardless of the venue or putative cause, says something about his judgment," Fred DeLorey, Conservative Party spokesman, said in an email. "The Liver Foundation is an extremely important cause, which many of our caucus were thrilled to support, albeit less ostentatiously."

Labour Minister Lisa Raitt, for example, attended the fundraiser. When the Trudeau ads first aired, she said the Liberal leader showed poor judgment.

"You wouldn't see me making that move, getting up on a walkway and taking clothes off in front of a bunch of men or women," she said.

"What would be the conversation today if that was a female MP who had done that in a room of men, guys? Why don't you think about that?"

The Liberals have responded to the ads with one of their own. Trudeau, a former teacher, is pictured in a classroom and he says he's not ashamed of his previous profession.

The Conservatives suggest in their ad campaign that he doesn't have the necessary experience to be prime minister. Trudeau calls on Canadians to stop finding flaws in each other and instead to work together to build a better country.

Use of 'copyrighted materials'

Meanwhile, former Liberal leader Stéphane Dion has sent a letter to Elections Canada to complain about the Conservative ads.

In the letter, Dion says the ads contain "unauthorized use of copyrighted materials" and notes the ads are being aired nationally, including in Labrador where a federal byelection is underway.

Dion suggests copyrighted material would normally require a licence fee for use, and asks the Commissioner of Canada Elections to rule on whether using the material amounts to a "non-monetary contribution" to the Conservative Party that should be considered a corporate donation, and therefore prohibited by Canada's elections law.