Despite coming under intense fire over what's been called his lack of transparency on Muskrat Falls cost issues, former Nalcor CEO Ed Martin refused to admit any wrongdoing during a tense day of testimony at a public inquiry Wednesday.

Inquiry co-counsel Barry Learmonth had sharp words for Martin, who he said kept the Nalcor board and the provincial government "in the dark" and denied government a chance to cancel or delay the project in 2013 by withholding critical financial information.

"I'm putting to you that you did the wrong thing," Learmonth stated.

"That you should have given this information to the government, with an explanation if you wanted to provide it, so that the government that was funding this project on behalf of the taxpayers would be in a position to make a decision as to whether they wanted to cancel this project or reassess the project.

"And you denied the government the opportunity to do that."

Martin said he disagreed, and that he would not go to government with cost and schedule information unless he was confident in the data prepared by his project team.

"I felt compelled to put together a package that was reasonably accurate so I knew if they made a decision on it I could say comfortably you had the right information, generally," Martin said.

Barry Learmonth is co-counsel at the Muskrat Falls inquiry. (Terry Roberts/CBC)

That's the way it went for most of the day, with Learmonth firing pointy questions, and Martin retorting with his own explanation of why certain decisions were made.

Early on, the two men behaved like alpha male teenagers sizing each other up in the schoolyard, but by the afternoon, Learmonth dropped the gloves by saying Martin was "not very good" at developing cost estimates, and that Martin "failed in his duty" keep government informed.

Martin did not lose his cool, however, although he seemed to grow increasingly frustrated at having to repeatedly answer the same question.

"How can [government] make a decision if they don't have the documents? If they're kept in the dark?" Learmonth said of a July 2013 report by the project team that forecast the cost for Muskrat at $800 million higher than the $6.2 billion sanctioning figure the year before.

The document was only revealed through the findings of a forensic audit done for the inquiry, and its existence was greeted with anger and shock during the testimony of some former politicians and senior bureaucrats.

Martin defended the decision to withhold the information, saying the estimate was still being finalized. But Learmonth shot back, saying Martin had a duty to disclose such alarming information to government, which was investing billions in the project.

Meanwhile, by the time the financing deal, including a federal loan guarantee, was finalized in late November 2013, the forecasted final cost had grown by $300 million, but a parade of government witnesses have testified they still believed the capital cost was $6.2 billion.

Learmonth and Martin sparred over whether this information was disclosed to the board and to the government, with both agreeing that commissioner Richard LeBlanc will have to decide whose testimony to believe.

Justice Richard LeBlanc is commissioner for the Muskrat Falls commission of inquiry. (Terry Roberts/CBC)

What's more, Learmonth said Martin was aware that some contract bids were coming in much higher than the project estimates in 2013, and did not disclose this information to government before the financing agreement was signed late in the year.

The timing, he suggested, is key, because this was the point-of-no-return on the project.

One expert has testified that if contract bids are higher than forecasted, a major project should be halted and re-evaluated.

"They were denied that opportunity," Learmonth said of government's final say on whether to proceed with Muskrat.

But again, Martin stood his ground, saying some were higher, and some were lower, and that all the information was eventually disclosed.

"They're not kept in the dark … they need me to give them information in a manner they can make a decision on," Martin said.

A central figure

Martin has been a central figure as the inquiry investigates why the troubled hydroelectric project is billions over budget and years behind schedule.

The tone of the day was set very early when Learmonth asked whether Martin upheld the values of honesty, trust and open communication while carrying out his duties as CEO.

"Is it your position that throughout your tenure at Nalcor … you personally adhered to and were guided by those core values and principles in your communications to the public and to the government of Newfoundland and Labrador?" asked Learmonth.

"Yes," Martin replied without pause.

Martin will continue testifying on Thursday, and if necessary, into Friday.

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