Update 1/19/2017: Our Children’s Trust, a legal NGO helping represent the youth case, posted that Rex Tillerson’s deposition is being delayed while the case’s lawyers meet to resolve a dispute.

Former ExxonMobil CEO Rex Tillerson, Donald Trump’s pick for Secretary of State, is set to be deposed today by lawyers for a group of 21 young plaintiffs, aged 9 to 20, who filed a lawsuit claiming the U.S. government failed to protect their rights to life, liberty, and property by not taking action to halt global warming.

The deposition comes just one day before Trump is to be inaugurated as U.S. president — and a little more than a week after a Massachusetts judge ruled that Exxon must hand over more than 40 years of its internal research on climate change, denying the oil giant’s request for a protective order that would have blocked Massachusetts Attorney General Maura Healey’s subpoenas.

“This affirms our authority to investigate fraud,” Healey tweeted after the judge’s decision was announced. “ExxonMobil must come clean about what it knew about climate change.”

An Exxon spokesperson told Reuters that the company was “reviewing the decision to determine next steps.”

Tamar Lawrence-Samuel, International Policy Director for Corporate Accountability International, responded to the news with a statement saying: “This is a huge victory for democracy and uncovering the truth about Exxon’s decades of deception and with Rex Tillerson poised to be the next U.S. Secretary of State, the timing couldn’t be better. This decision could help expose not only what Exxon knew and covered up in the past but also what kind of activities and denialism it continues to fund to undermine climate action.”

The company has already complied with a subpoena issued by New York Attorney General Eric Schneiderman by turning over thousands of pages of documents. Healey and Schneiderman are among the 20 state attorneys general investigating Exxon after investigative reports from InsideClimate News and the LA Times suggested that Exxon has known about the dangers of global warming for decades, but covered up its internal research and embarked on a campaign of misinformation about climate science in order to delay action.

Last April, DeSmog uncovered Exxon corporate documents from the late 1970s stating, “It is assumed that the major contributors of CO2 are the burning of fossil fuels … There is no doubt that increases in fossil fuel usage and decreases of forest cover are aggravating the potential problem of increased CO2 in the atmosphere.” Despite the conclusions of its own scientists, the company engaged in efforts to lobby the government against emissions regulations while funding climate change denial, according to multiple reports.

During a contentious confirmation hearing before the Senate, Tillerson repeatedly dodged questions from Virginia Senator Tim Kaine about what Exxon’s scientists knew regarding fossil fuels’ role in driving global climate change.

In today’s deposition, he’s likely to hear very similar questions — however, this time he’ll be under oath.

“What did you know and when did you know it?” Julia Olson, the lead attorney for the youth suing the federal government over its inaction on climate change, told Business Insider those are the questions she plans to ask Tillerson. She goes on from there:

Once you knew it, what did you do with that information? What did you tell the government? And then, what are the things you did to keep our national energy policy and system dependent upon fossil fuels? And what role did you play with the government in critical decisions at different points to ensure that we did not transition away from fossil fuels, even though you knew it was necessary to preserve our climate system?

In November, a federal judge denied the U.S. government’s motion to dismiss the lawsuit, meaning the children and young adults’ suit will go to trial in federal court in Oregon, likely later this year.

Several fossil fuel industry groups legally intervened in the youth plaintiffs’ suit against the federal government, including the American Petroleum Institute, for which Tillerson once served as chairman and sat on the board of directors. That means that, if he does become Trump’s Secretary of State, he will be in the peculiar position of being part of the defense as a member of the industry groups that intervened, in addition to his involvement as a member of the federal government.

But when under oath in a federal lawsuit, Tillerson will most likely have to be more forthcoming than he was during his confirmation hearing before the Senate — and the information he is compelled to divulge could come back to haunt him as Secretary of State, given the number of states that are investigating whether Exxon knowingly misled the public and its shareholders under Tillerson’s tenure as chief executive.

Oil Change International campaigns director David Turnbull told EcoWatch that “the prospect of a sitting secretary of state becoming entangled in a lawsuit for his role in misleading the public about climate change is as real as it is alarming.”

Turnbull added that Tillerson should stop being evasive and simply make public all of the documents Exxon provided to New York Attorney General Schneiderman, so that the public would have the full account of his role in the company’s disinformation campaign. “Anything short of that will leave questions looming that evidence suggests may only be later answered in court,” he said.

Main image: Caricature of Rex Tillerson Credit: DonkeyHotey, CC BY 2.0