After weeks of speculation over what exactly went on in the SNC-Lavalin affair, former attorney general Jody Wilson-Raybould will be in the hot seat on Wednesday.

Members of the House of Commons justice committee will be trying to gather as many facts as possible during her appearance this afternoon about the allegations published by The Globe and Mail that she was pressured to intervene in the case of SNC-Lavalin to spare the Montreal engineering firm a criminal trial and potential conviction for corruption and fraud — and the decade-long ban on bidding for government contracts that would come with it.

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While Prime Minister Justin Trudeau has called the allegations “false,” Wilson-Raybould has remained largely silent, neither confirming nor denying key claims that officials in Trudeau’s office pressured her to step in and get public prosecutors to cut the firm a remediation agreement.

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She claims solicitor-client privilege prevents her from commenting and two weeks ago retained former Supreme Court justice Thomas Cromwell to advise her on what she can and cannot talk about.

Her hotly-anticipated appearance could either reveal new details about the case or leave Canadians still scratching their heads.

Here are several of the most pressing questions she will likely face.

Who said what and when?

At the heart of the SNC-Lavalin affair are what can be described as the known unknowns: the things we know we do not know.

While the initial report alleged PMO officials pressured Wilson-Raybould, it is not known who specifically may have been involved, what they may have said and when they may have said it. Testimony last week by Clerk of the Privy Council Michael Wernick put the focus on three meetings that Wilson-Raybould will likely be asked about extensively.

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First, there’s the meeting on Sept. 17 between Wilson-Raybould, Trudeau and Wernick, two weeks after the director of public prosecutions decided on Sept. 4 that SNC-Lavalin was not eligible for a remediation agreement to keep its case from going to trial.

Second, there’s the meeting three months later on Dec. 18 between Jessica Prince, the former attorney general’s chief of staff, and unknown staff from the PMO.

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And third, there’s the meeting the next day on Dec. 19 between Wilson-Raybould and Wernick, in which the latter raised concerns with her that were apparently being expressed from the highest levels of government about her decision not to intervene in the decision of the public prosecution service.

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“I conveyed to her that a lot of her colleagues and the prime minister were quite anxious about what they were hearing and reading in the business press about the future of the company, the options that were being openly discussed in the business press about the company moving or closing,” Wernick said at the justice committee last week.

“I can tell you, with complete assurance, that my view of those conversations is that they were within the boundaries of what’s lawful and appropriate.” Tweet This

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But certain recent grenades have been dropped into the discourse around what exactly happened: chief among them, the stunning resignation of Trudeau’s principal secretary, Gerald Butts, on Feb. 18.

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Though his letter of resignation said that “any accusation that I or the staff put pressure on the Attorney General is simply not true,” the move immediately sparked questions that remain unanswered about what role, if any, he may have played in the matter, particularly in the meeting with Prince and PMO officials.

In short: expect plenty of questions to focus on trying to nail down who exactly may have been involved and what specifically might have been said, which leads to the next likely topic of interest for the committee.

Why did Wilson-Raybould resign?

What we know so far is that Wilson-Raybould resigned publicly on Feb. 12 but gave her letter of resignation to Trudeau on Feb. 11, just hours after he made public comments suggesting that her continued presence in his cabinet amid the SNC-Lavalin affair meant everything was fine.

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Her letter, posted on her website, contained few details but raised plenty of questions.

In it, she made only the barest mention to the controversy engulfing the government.

READ MORE: Justin Trudeau’s top adviser Gerald Butts resigns amid SNC-Lavalin affair

“I am aware that many Canadians wish for me to speak on matters that have been in the media over the past week,” she wrote.

“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 the Honourable Thomas Albert Cromwell, CC as counsel.”

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She continued, adding that “regardless of background, geography or party affiliation, we must stand together for the values that Canada is built on, and which are the foundation of our future.”

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When asked about the matter, Trudeau has consistently told reporters that he remains “surprised and disappointed” by her decision to step down.

But the void of clear explanations will likely see committee members, particularly from the opposition Conservative and NDP members, hammering Wilson-Raybould for more details and specifically, for a clearer accounting of whether she did, in fact, feel pressured by any of the meetings with officials.

What counts as pressure — and when does it cross the line?

This really is one of the most significant questions members will likely be trying to deal with.

What, if anything, in her interactions with Trudeau, Wernick, Butts, or any other senior government officials, might have left her feeling pressured?

And if she or her staff did feel pressured, at what point — again, if any — did Wilson-Raybould come to believe this crossed the line?

Did she raise these concerns with anyone? Trudeau has indicated in multiple remarks to media that she did not raise concerns with him. Committee members may be keen to push this one step further, though, to figure out whether she raised concerns with anyone else — outside legal counsel, for example.

READ MORE: Government has a responsibility to defend jobs, Trudeau says amid SNC-Lavalin allegations

On Monday night, the government waived limited aspects of solicitor-client privilege and cabinet confidentiality to allow Wilson-Raybould to speak to both the justice committee and the ethics commissioner about what went on. But there are still some things she cannot talk about: any conversations she may have had with the director of public prosecutions about the case, for example.

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One thing at this point seems certain: no matter what Wilson-Raybould says, her testimony is likely to spark even more questions.

What remains to be seen is where they will lead next.

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