The prosecution of SNC-Lavalin is proceeding full-steam ahead, with a preliminary hearing already underway in Montreal. A criminal trial is possible within a year.

That is unless the Trudeau government hands the Quebec company a get-out-of-jail-free card in the form of a much-talked-about deferred prosecution agreement.

If a DPA is granted, there won't be a trial and Canadians may never hear how far up the corporate ladder the alleged corruption went inside the global engineering firm.

And with the current parliamentary hearings so narrowly focused on the "he said, she said" of the Prime Minister's Office and the former attorney general, Canadians are at risk of never learning the full extent to which SNC-Lavalin may have influenced the government.

1. How widespread was the bribery?

The criminal case looming over SNC-Lavalin is specifically about Libya.

The company is accused of paying $48 million in bribes to Libyan officials, with executives alleged to have bankrolled yachts and prostitutes for the son of former dictator Moammar Gadhafi in a bid to win lucrative contracts in the country.

If SNC-Lavalin is granted a remediation agreement, the company would face a massive fine — but the public will never get to see the evidence that the RCMP and prosecutors have spent seven years amassing in anticipation of the criminal trial.

What we don't know — and may never know — is the extent of corruption beyond Libya.

SNC-Lavalin is alleged to have paid millions for travel, hotels and escorts on trips to Toronto and Montreal for Saadi Gadhafi, the son of Libya's former dictator, shown here in a 2005 file photo. (Tim Wimborne/Reuters)

A CBC News and Globe and Mail investigation in 2013 revealed SNC-Lavalin used secret codes in budgets to hide improper payments on projects around the globe, which numerous employees allege were for bribes. The investigation exposed the payments in 13 countries, including Nigeria, Zambia, Uganda, Ghana, India and Kazakhstan.

But Canada has yet to convict anyone from SNC-Lavalin for any foreign bribery — something that is illegal under Canadian law, which aims to stop Canadian companies from propping up corrupt officials and dictators in some of the world's most underdeveloped, oppressive regimes.

A trial in the Libya case could be the last chance for accountability through a public and open hearing.

2. What did SNC's senior management know?

SNC-Lavalin's former top construction executive, Riadh Ben Aïssa, has already pleaded guilty to bribing Libyan officials and laundering tens of millions of dollars in kickbacks through Swiss bank accounts to win billions in contracts.

But that was in Switzerland, where he was jailed for two-and-a-half years.

What we don't know is who else was involved.

Former SNC executive vice-president Riadh Ben Aïssa, right, pleaded guilty in Switzerland in 2014 to paying bribes to Saadi Gadhafi, left, in order to land lucrative contracts. The company has said he was a rogue employee. (Radio-Canada)

Ben Aïssa has since become a key witness for the prosecution in the upcoming Canadian trial. He's ready to point fingers at others in the company who, for years, groomed and promoted him. He can testify about who in the senior ranks knew about the alleged bribery, and SNC-Lavalin's frequent use of shell companies and Swiss bank accounts to pay "agents" to win global projects.

SNC has long argued that Ben Aïssa was a rogue actor. It denies the charges it is currently facing in Canada.

"All the sources of our troubles [are] coming from him," Jacques Lamarre, SNC-Lavalin's CEO from 1996 until 2009, told CBC News in 2014.

Granting SNC-Lavalin a DPA would shut down Ben Aïssa's testimony.

3. What happened in the Gadhafi smuggling plot?

One of the more bizarre twists in the SNC-Lavalin saga involves two Canadians tied to a plot to smuggle Saadi Gadhafi — the son of the late Libyan dictator and a longtime SNC-Lavalin patron — into Mexico.

In 2011, as civil war toppled the Libyan regime, SNC-Lavalin scrambled to save its projects in the country, as well as its profitable patronage with the Gadhafi family.

Canadian consultant Cynthia Vanier and SNC-Lavalin vice-president Stéphane Roy were detained by police in Mexico City, the pair among a group accused of a conspiracy to forge passports and fly Saadi Gadhafi and his family to a life in hiding.

Canadian consultant Cynthia Vanier spent 18 months in a Mexican prison, accused in a plot to smuggle Saadi Gadhafi and his family out of Libya. But she was released after a court ruled her legal rights had been violated. (Submitted by Betty MacDonald)

But Canadians have never heard the full story.

Vanier, accused of being the mastermind of the plot, was imprisoned in Mexico for 18 months. But she was released after a court ruled her legal rights had been violated.

Back in Canada, the RCMP charged Roy in 2014 in relation to the caper and SNC's Libya dealings. But his entire case was thrown out last month due to delays.

SNC-Lavalin has argued Roy and Vanier were rogue actors, and have launched lawsuits against them.

The Gadhafi smuggling plot will no doubt be evidence at the company's upcoming trial.

4. Have lobbyists swayed the Trudeau government?

SNC-Lavalin CEO Neil Bruce, named to that post in 2015, vehemently denies the allegations against the company.

"We've done nothing wrong as a company and none of our current employees have done anything wrong," Bruce told investors last month.

"We've never asked that the charges be dropped, we've never asked for anything to be circumvented outside this judicial system."

Yet Bruce and others from SNC-Lavalin have been vigorously lobbying the Trudeau government for a way out.

SNC-Lavalin CEO Neil Bruce addresses shareholders during the company's annual general meeting in Montreal on May 3, 2018. In an interview with Bloomberg late last year, Bruce said the pending litigation against SNC has cost his company some $5 billion from lost contracts. (Graham Hughes/Canadian Press)

The company has lobbied federal officials on 60 different occasions, pressing the government, among other things, for deferred prosecution and to relax the penalties for corporations convicted of foreign bribery.

What we don't know is what was said or what influence SNC-Lavalin's ear-bending may have had on the prime minister, the PMO, or officials within the justice system.

The House of Commons justice committee is currently narrowly focused on the allegations that the PMO attempted to politically interfere in the prosecution of SNC-Lavalin by pressuring Jody Wilson-Raybould to offer a DPA. And the federal ethics commissioner is also probing the issue.

But there is no formal probe into how this criminally charged corporation has potentially influenced the government through its extensive lobbying.

5. What about SNC's illegal political donations?

Amid the latest political drama, few are talking about SNC-Lavalin's long history of illegal political donations.

Back in 2013, CBC News caught SNC-Lavalin making illegal donations to federal parties when executives were instructed to donate to certain candidates, only to be reimbursed through company bonuses.

The Commissioner of Canada Elections investigated, charging a lone SNC-Lavalin bagman who pleaded guilty in November to illegally funnelling $117,000 to the Liberal and Conservative parties.

But we don't know who else was involved, or the kind of influence SNC-Lavalin expected or may have received in exchange for their illegal donations.

The elections watchdog gave the company a pass, agreeing to a compliance agreement in 2016 that closed the case. That lone executive paid a $2,000 fine.

Under the compliance agreement, the commissioner of Canada elections agreed to not pursue other "certain former senior executives" and didn't prosecute anyone within the political parties, allowing them to simply pay back the money.

Send tips to dave.seglins@cbc.ca or rachel.houlihan@cbc.ca.