Photo: The Canadian Press

Canada's conflict of interest and ethics commissioner is launching an investigation into Prime Minister Justin Trudeau's recent family holiday at the Aga Khan's exclusive private island in the Bahamas.

Mary Dawson says Trudeau may have violated the federal ethics code during his holiday with the Aga Khan, a family friend, noted philanthropist and hereditary spiritual leader to the world’s approximately 15 million Ismaili Muslims.

It's the first time the commissioner has opted to investigate the actions of a sitting prime minister.

In a letter to Conservative MP Blaine Calkins, one of those who filed formal complaints, Dawson says she is looking into both Trudeau's stay at the island and his use of the Aga Khan's private helicopter to get there.

"I am of the view that your request satisfies the requirements set out in subsection 44 (2) of the (Conflict of Interest) Act," Dawson writes.

"I have therefore commenced an investigation ... to determine whether Mr. Trudeau has contravened sections 11 and 12 of the Act in connection with his recent stay at and travel to the Aga Khan's privately owned island."

The vacation included Trudeau, his family, Liberal MP Seamus O'Regan and Liberal party president Anna Gainey, all of whom took part in the chopper flight in Nassau in order to get to the secluded island.

Both the Conflict of Interest Act and Trudeau's own ethics guidelines bar the use of sponsored travel in private aircraft, allowing it only for exceptional circumstances related to the job of prime minister and only with the commissioner's prior approval.

The guidelines also prohibit a minister or any member of their family from accepting gifts or "advantages" that could reasonably be seen as influencing government decisions. The only exception is if the person providing the gift is a friend.

Trudeau has repeatedly called the Aga Khan a longtime family friend who was a pallbearer at his father's funeral.

Dawson's letter says she will decide whether the two are friends as defined in legislation "to determine the acceptability of the gift."

The prime minister, who was scheduled to take part in a public town hall later Monday in Dartmouth, N.S., has defended his actions multiple times, saying he stands ready to meet with Dawson about the trip.