The additional information on the SNC-Lavalin affair that former justice minister and attorney general Jody Wilson-Raybould provided to a House of Commons committee Friday revealed a few interesting twists in a controversy that has had politically minded Canadians gripped for the past two months.

They include a suggestion that former prime minister Brian Mulroney once interfered in the course of justice on behalf of David Milgaard, and shed light on why Wilson-Raybould really resigned from the federal cabinet and why she said she has nothing else to offer that will further help people understand her perspective of the SNC-Lavalin affair.

A recording made by Jody Wilson-Raybould of a 17-minute Dec. 19 call between herself and Privy Council Clerk Michael Wernick has been released. This, the latest in the unraveling SNC-Lavalin controversy that has the former attorney general pitted against Prime Minister Justin Trudeau. 5:43

1. Kim Campbell and Brian Mulroney

Wilson-Raybould provided a transcript of a text conversation she had with her former chief of staff Jessica Prince after Prince met to discuss SNC-Lavalin with Prime Minister Justin Trudeau's chief of staff Katie Telford and former principal secretary Gerry Butts.

In that transcript Prince said Butts made the case to her that a prime minister can order an attorney general to revisit a decision in the interests of justice.

The example that was used, according to Prince's account of the meeting, is that Butts referenced an action taken by Mulroney after he met with the mother of David Milgaard.

Wilson-Raybould says she met with Campbell on Dec. 19 to discuss the case of Milgaard, seen here in the centre in 2005, who spent 23 years in prison before being exonerated and released. (Geoff Howe/Canadian Press)

Milgaard, who was wrongly convicted of rape and murder, was still in prison at the time. The attorney general was future prime minister Kim Campbell who, according to Prince's account, said that she could not revisit the decision to review Milgaard's case because to do so would be to "interfere in an independent process."

"But then I think she ultimately ordered the [Supreme Court of Canada] to look at his case," the transcript says. "It was because Mulroney told her that she had to find a solution."

The transcript then shows Wilson-Raybould asking her chief of staff for Campbell's contact details.

Wilson-Raybould says she met with Campbell on Dec. 19 to discuss the Milgaard case.

"She categorically denied what Mr. Butts had said and was quite offended and outraged by the comments," the documents say.

They add that Campbell denied the characterizations of her and Brian Mulroney.

Attempts by CBC News to reach Campbell were unsuccessful.

2. Why Wilson-Raybould resigned from cabinet

Wilson-Raybould also shed light on the reason she stepped down from her position as minister of veterans affairs.

In her letter to the committee, Wilson-Raybould revealed that, while it was her initial suspicion that the decision to move her from her post as the minister of justice and attorney general was because she refused to grant SNC-Lavalin a deferred prosecution agreement, she later changed her thinking on that.

The resignation of Jody Wilson-Raybould from the Liberal cabinet was a significant development in the SNC-Lavalin affair, a controversy that has now sparked two government-related probes and continues to dog Prime Minister Justin Trudeau. (Sean Kilpatrick/Canadian Press)

"After much reflection, I decided to take the prime minister at his word that this was not the case, and accept a post I was honoured to have as the minister of veterans affairs," she said.

When the Globe and Mail published a story alleging that Wilson-Raybould felt she was inappropriately pressured by Prime Minister's Office staff, the former justice minister remained quiet.

In her letter, Wilson-Raybould said that when Trudeau told reporters on Feb. 11 that her continued presence in cabinet should "speak for itself" on what the former attorney general thought of the allegations, she resigned.

"The prime minister stated publicly, when issues about the propriety of the government's conduct in relation to the SNC matter arose, that my ongoing presence in cabinet spoke for itself. I resigned the next day, and I trust my resignation also speaks for itself."

3. Nothing more to add

The Clerk of the Privy Council, Michael Wernick, first testified before the justice committee on Feb. 22. Wilson-Raybould gave her testimony on Feb. 27 with Wernick returning on March 6 to answer some questions, some of which were about why his account of a Dec. 19 phone call with Wilson-Raybould did not exactly match with testimony given by the former justice minister.

Ever since Wilson-Raybould first appeared before the committee, the opposition has been calling on the Liberal government to allow her to come back to committee for further questioning. The opposition also wanted to speak to Wilson-Raybould about why she stepped down as minister of veterans affairs.

During her appearance before MPs, Wilson-Raybould told the committee that she could not explain why she stepped down from cabinet, because to do so would violate the waiver Trudeau had given her to break cabinet confidence and attorney-client privilege to discuss issues related to SNC-Lavalin only.

The Conservatives even staged a parliamentary stunt holding MPs in the House of Commons for a day and a half on a series of votes to pressure them to let Wilson-Raybould speak before committee again.

The NDP has repeatedly called for a public inquiry to get to the bottom of the matter.

Former cabinet minister Jane Philpott joined the fray, giving an interview in Maclean's magazine saying that "there's much more to the story that needs to be told."

But in her letter to the Justice committee on Friday, Wilson-Raybould suggested she has nothing else to say on the matter.

"I do not believe I have anything further to offer a formal process regarding this specific matter, though of course if compelled or asked to participate in a judicial, investigative or parliamentary process I would do so," she said.