Last week, the Globe and Mail newspaper alleged, based on unnamed sources, that the prime minister's office had pressured Jody Wilson-Raybould to intervene in the case against the Quebec-based engineering giant.
Then he said she had reconfirmed a conversation the pair had last fall in which he told her that the final decision in any federal prosecution was hers alone. "I am in the process of obtaining advice on the topics that I am legally permitted to discuss in this matter, and as such have retained Honerable Thomas Albert Cromwell, CC as counsel", Wilson-Raybould wrote in the letter.
Shortly before her resignation announcement, the Union of British Columbia Indian Chiefs issued an open letter to Trudeau demanding that he publicly condemn "the racist and sexist innuendo" that's circulated about Wilson-Raybould since her demotion, suggesting that she's hard to work with and not a team player.
For her part, Ms. Wilson-Raybould remained mostly silent, invoking attorney-client privilege as her reason for not commenting on the issue.
Jody Wilson-Raybould, Canada's Minister of Veterans Affairs and Associate Minister of National Defence, has announced she is resigning from her position in Prime Minister Justin Trudeau's cabinet.
"We urge Mr. Trudeau's team to stop trying to discredit Ms. Wilson-Raybould and to commit to fully cooperate with the Ethic Commissioner's investigation".
Wilson-Raybould will, however, be staying on as an MP in Vancouver-Granville.
On Monday, Canada's independent Conflict of Interest and Ethics Commissioner confirmed he had launched an examination into the allegations following a request from two opposition New Democrat MPs.
Time will tell if there will be any continued political fallout on the issue, but, with the SNC-Lavalin issue still percolating, it's another headache the PM doesn't need.
In a similar fashion, the Director of Public Prosecutions Act gives the attorney general, a politician, the power to override the decisions of federal prosecutors.
Does that mean the Liberals will allow the committee to hear from Wilson-Raybould?
"In our system of government, of course, her presence in cabinet should actually speak for itself", he said following a housing announcement - one that Wilson-Raybould didn't attend, unlike a handful of fellow Liberals from the city.
The PM says nothing illegal happened; if so, he could fix this by letting his former attorney general speak.
The prime minister defended his government's record on reconciliation in a warehouse of buses Tuesday after Indigenous leaders accused him of throwing one of his former ministers under one.
It shouldn't be lost on anyone that the former attorney general has hired a retired Supreme Court justice to advise her.
Wilson-Raybould's resignation could not possibly be unfolding in a manner more damaging to the election-year aspirations of Justin Trudeau, whose ways, in recent days, seem to have taken a deliberate turn from sunny to murky.
Reporters at the Winnipeg event asked Trudeau if he supports a Justice Committee investigation, and if he will testify as Conservatives have called for.
Wilson-Raybould hasn't spoken about those allegations, which could amount to obstruction of justice charges for someone in the PMO.
"The current Liberal brand has been taking a beating on this portfolio", she said.
"I'm absolutely pissed", said Stewart Phillip, president of the Union of British Columbia Indian Chiefs.
He added he remains "concerned about the many unanswered questions" surrounding her resignation.