He declined to say whether he had advised any state legislatures — which have become hubs for Republican efforts to push claims of election fraud — on voting issues. And he insisted that his two-page memo, which he said he hastily wrote while on Christmas vacation with his family in Texas, had been taken out of context, but defended his view that Mr. Pence could have done far more to help Mr. Trump.
“I won’t be cowed by public opposition to it,” Mr. Eastman said.
He added: “There are lots of allegations out there that didn’t get their day in court and lots of people that believe them and wish they got their day in court. and I am working very diligently with several teams — statistical teams, election specialists teams, all sorts of teams — to try and identify the various claims and determine whether they have merit or there is reasonable explanation for them.”
Like many of the lawyers who worked in Mr. Trump’s administration, Mr. Eastman had strong conservative legal credentials, initially giving him a patina of respect in Mr. Trump’s inner circle.
Mr. Eastman attended law school at the University of Chicago and clerked for both Justice Clarence Thomas of the Supreme Court and Judge J. Michael Luttig, a former federal appeals court judge who President George W. Bush considered for the Supreme Court. He is a member of the conservative Federalist Society and a former dean of the law school at Chapman University in Orange County, Calif. For two decades, he ran his own small law firm that focused on representing conservatives on issues like free speech, religious liberty, abortion and immigration.
After Election Day, Mr. Eastman served as a behind-the-scenes legal quarterback of sorts for Mr. Trump, alarming some of Mr. Trump’s aides, who feared he had found someone to enable his worst instincts at one of the most dangerous moments of his presidency. And it surprised many of Mr. Eastman’s longtime friends and others, who questioned whether his access to power had skewed his vision of reality.
“You’re always at risk when every fail-safe mechanism breaks down,” Mr. Bolton said.
Mr. Eastman’s role in Mr. Trump’s efforts to remain in power began the weekend after the election in Philadelphia, where Mr. Eastman had traveled for an academic conference. At a nearby hotel, Mr. Trump’s closest aides, including Corey Lewandowski, were putting together a legal brief to challenge the results in Pennsylvania.
Mr. Eastman had put himself on the radar of Mr. Trump’s political aides during the election when Jenna Ellis, a legal adviser to Mr. Trump’s campaign, had shared on Twitter an article Mr. Eastman had written. The article, in an echo of racist questions stoked by Mr. Trump about where President Barack Obama had been born, questioned whether Kamala Harris, Mr. Biden’s running mate, could legally become president because her parents had not been born in the United States.