NOTE: This story has been updated to include further response from the RCMP.

The Royal Canadian Mounted Police should have recused themselves from deciding whether Prime Minister Justin Trudeau should be investigated in connection with his controversial vacation on the Aga Khan's island because the national police service owed the island's managers money and its officers took part in the trip, says Conservative MP Pierre Poilievre.

Instead of rejecting a call for an investigation into whether Trudeau broke the law by receiving a benefit from someone who had dealings with the government, the RCMP should have turned the question over to another police force, said Poilievre.

"The RCMP has a lot of explaining to do. It is a criminal offence for a government official to accept a benefit from someone who has government business," Poilievre told CBC News on his way into Wednesday's Conservative caucus meeting.

"Mr. Trudeau did exactly that. We filed a criminal complaint with the RCMP to investigate it and instead of doing the honourable thing, which would have been to refer the matter to another police agency that is not implicated in the issue, the RCMP simply killed it and refused to investigate it."

However, in an email sent to CBC News several days after the initial publication of this story, the RCMP defended its decision not to launch an investigation into the Bahamas trip.

"The RCMP's Sensitive and International Investigations team has thoroughly reviewed the matter and a decision was taken internally to not pursue a criminal investigation," the RCMP said in the email. "The RCMP takes all complaints seriously and decisions are reflective of the thoroughness, diligence and independence of our investigations."

While RCMP officers participated in the trip, the decision about investigating was made independently, the force added.

"The RCMP is aware of the perception of bias associated with its dual mandates of protecting Canadian dignitaries as well as its investigative mandate with respect to politically-sensitive matters," the RCMP wrote. "The RCMP's operations are entirely independent and completely free from any government influence. Additionally, a separation is made between its internal resources to ensure that its investigations are conducted in a professional and objective manner."

Poilievre's comments came after CBC News revealed that the RCMP had yet to repay the managers of the Aga Khan's island more than $56,000 for accommodations, meals and jet ski rentals during Trudeau's vacation on Bell Island three years ago.

RCMP Commissioner Brenda Lucki sent Conservative MP Peter Kent a letter saying the RCMP had concluded it could not have a productive investigation into whether Prime Minister Justin Trudeau's trip to the Aga Khan's island broke the law. (Sean Kilpatrick/Canadian Press)

While the RCMP decided the costs should be reimbursed, their efforts to pay the tab have been stymied by the government's financial rules and the refusal of the managers of the Aga Khan's island to issue a formal invoice for the expenses the RCMP incurred.

Overall, Trudeau's vacation on the Aga Khan's island cost Canadian taxpayers more than $215,000, with the RCMP accounting for $153,504 of the tab. The RCMP have not yet responded to questions from CBC News about whether the $56,000 they have yet to pay for meals, accommodations and jet ski rentals is included in that amount.

Trudeau has repeatedly come under opposition attack for taking the trip to the Aga Khan's private island in the Bahamas over the Christmas holidays in 2016/17.

Then-ethics commissioner Mary Dawson found in December 2017 that Trudeau violated four sections of the Conflict of Interest Act, which governs public office holders, when he accepted the vacation from the Aga Khan. She rejected Trudeau's argument that the Aga Khan, whose foundation and Global Centre for Pluralism deal with the federal government, was simply a family friend and said the vacations could be perceived as an attempt to influence Trudeau.

A separate case, which centres on the question of whether the Aga Khan violated Canada's lobbying rules, is to be heard by the Federal Court of Appeal on Dec. 12.

Prime Minister Justin Trudeau meets with the Aga Khan on Parliament Hill in Ottawa on Tuesday, May 17, 2016, a few months before his vacation on Bell Island. (Sean Kilpatrick/Canadian Press)

In May, Conservative critic Peter Kent called for the RCMP to look into the trip to the Aga Khan's island, citing a provision of the Criminal Code that prohibits public officials from accepting a benefit from someone who has dealings with the government.

But in a letter to Kent dated Aug. 19, RCMP Commissioner Brenda Lucki informed him the force reached the conclusion it could not "productively pursue a criminal investigation."

Poilievre said he would like the RCMP complaints commission to investigate how that decision was handled.

"The fact that they have ongoing financial implications of their own with the Aga Khan's island shows that they were in a conflict of interest in deciding whether or not to open a criminal investigation," he said.

Poilievre said others have faced criminal charges for less.

"The RCMP charged Mike Duffy for receiving a benefit," he said. "Well, Justin Trudeau received a benefit of much greater value from someone who was seeking a $15 million grant from his government. There are sections of the Criminal Code that apply precisely to what happened, yet the RCMP has done absolutely nothing to examine whether charges should be laid."

Michael Barrett, Conservative ethics critic, said he wants Parliament's ethics committee to hold hearings into Trudeau's trip to the Aga Khan's island and the RCMP's decision not to investigate.

A house on Bell Island, the Bahamas. (CBC)

In the upcoming minority Parliament, the Liberals will no longer command a majority on committees.

NDP Leader Jagmeet Singh said the trip to the Aga Khan's island speaks to a disconnect between Trudeau and what Canadians are going through as they try to make ends meet.

"I think that Mr. Trudeau has a lot to answer for. He should answer these questions. He created this problem in the first place and has been found to have breached the ethics code."

Elizabeth Thompson can be reached at elizabeth.thompson@cbc.ca