The Conservatives have accused Justin Trudeau of "lacking any decency," saying he refused to reimburse a charity that lost money after it paid him to speak at a fundraising event.

The Grace Foundation of Saint John, N.B. waited almost a year to ask Trudeau to return his $20,000 speaker's fee. It described "An Evening with Justin Trudeau" as a success on its website a week after he spoke.

Trudeau, through a Toronto-based organization called Speakers' Spotlight, has garnered hefty fees speaking at various events. Although he started this part of his career before he was elected, he continued while he was an MP.

Last June 27, he was hired by the Grace Foundation to speak about empowerment and youth at the Imperial Theatre in Saint John.

The event was "a huge disappointment and financial loss," for the organization according to a March 6 letter to Trudeau from Grace Foundation board member Susan Buck, which was given to CBC News by a spokesperson for the Prime Minister's Office.

In the letter, Buck asked Trudeau for a refund. There is no mention of why she waited nine months to contact him.

120 tickets sold for Trudeau speech

Information provided by the Prime Minister's Office says Trudeau was paid $20,000 by the Grace Foundation plus travel costs, meals and accommodation. Tickets for his speech were $50 and 120 were sold for a total of just $6,000, but there was no refund from Trudeau.

CBC News was unable to reach Buck on Friday. Attempts to reach other board members of the Grace Foundation, as well as its president, were also unsuccessful.

On its website, the Grace Foundation describes itself as a charitable organization that supports the Church of St. John and St. Stephen Home, a licensed 80-bed seniors' residence in Saint John. Its fundraising operation, the foundation says, provides "additional programs, activities and assistance" for the residents.

A week after Trudeau spoke, a newsletter from the Grace Foundation thanked several corporate sponsors, including RBC Dominion Securities and National Leasing, for contributing to the "success of Grace Foundation's first fundraising event." There is no mention that the event was a bust.

However, a PMO spokesperson said in an email Friday that the charity "incurred a massive $21,000 financial loss, and ultimately let a staffer go because of this."

In question period in the House of Commons on Friday, Immigration Minister Jason Kenney, standing in for the prime minister who is on a European visit, said Trudeau was getting paid $160,000 as an MP, "but he went and took a $20,000 cheque from a group of seniors trying to do a fundraiser to buy furniture."

The Liberal leader was not in the House to respond.

But in an email, Kate Monfette, a spokesperson for Trudeau, expressed surprise that the Grace Foundation was unhappy, noting the group "did not contact anyone for reimbursement until almost one year after the event," and had "previously indicated that they were satisfied."

During the leadership campaign, Trudeau opened his personal finances to the Ottawa Citizen newspaper, saying in his "best year" his private public-speaking business earned more than $450,000. In 2012, he earned $72,000 for four speaking events.

He has said he gave up his public speaking business once he decided to run in the Liberal leadership race.