Donald Trump. Getty Images Reports that President Donald Trump pressured FBI Director James Comey in February to drop the bureau's investigation into Michael Flynn, the former national security adviser, have led lawmakers and legal experts to question whether Trump obstructed justice — a criminal and impeachable offense.

The New York Times reported Tuesday that Comey wrote a memo about his meeting with Trump on February 14, one day after Flynn was asked to resign. The document "was part of a paper trail Mr. Comey created documenting what he perceived as the president's improper efforts to influence a continuing investigation," The Times reported.

"I hope you can see your way clear to letting this go, to letting Flynn go," Trump told Comey, according to the memo reported by The Times.

The FBI is investigating Flynn's contacts with Russia's ambassador to the US, Sergey Kislyak, as part of its probe into Russia's interference in the 2016 election. The bureau interviewed Flynn about his conversations with Kislyak in January.

Obstruction of justice is broadly defined: It involves any conduct in which a person willfully interferes with the administration of justice.

But to charge Trump with obstructing justice based on the Comey memo alone would not be an easy case, said Robert Deitz, a former senior counselor to the CIA director and former general counsel at the National Security Agency. That is primarily because it is unclear whether Trump was ordering Comey to end the FBI's investigation into Flynn or asking Comey if he would consider dropping the case because Flynn was "a good guy."

According to CNN's Jake Tapper, Comey didn't resign or go to the press after Trump made the request because he didn't see it as "a very successful effort" and he "thought he'd pushed back on it."

Legal and national-security experts at Lawfare have also said that to charge someone with obstructing justice, prosecutors have to prove that "the defendant corruptly endeavored to influence, obstruct, or impede" an investigation. That element "is the hardest to prove, because it depends on showing an improper motive," the experts said.

But there are a couple of important caveats.

'The president fired the FBI director'

According to The Times' report of Comey's memo, Trump asked Attorney General Jeff Sessions and Vice President Mike Pence to leave the room before he asked the FBI director to drop the investigation into Flynn's contacts with the Russians. That, according to Lawfare, "may indicate intent."

Jeffrey Toobin, a CNN legal analyst, agreed that Trump's request for Pence and Sessions to scram "suggests consciousness of guilt." Susan Hennessey, a former NSA attorney, told CNN on Tuesday that "if any part of Trump's intention here was to interfere with the investigation, that's going to qualify as obstruction."

Trump's conversation with Comey was part of a broader pattern that could more easily open him up to charges of obstruction of justice, experts say, beginning with Trump's reported requests for Comey to pledge his loyalty and assurance that he wasn't under FBI investigation and ending last week when he fired Comey.

"Historically, obstruction-of-justice articles of impeachment do elaborate a pattern of conduct," the legal experts at Lawfare wrote. "The first article of impeachment against Richard Nixon, for instance, included making false statements to investigators, withholding evidence, counseling witnesses to lie or give misleading testimony, and 'interfering or endeavoring to interfere with the conduct of investigations by the Department of Justice of the United States and the Federal Bureau of Investigation.'"

Days after he fired Comey, Trump told NBC's Lester Holt that he asked the FBI director three times if he was being investigated by the bureau as part of its probe into Russia's election interference.

"Not every day the president flirts with outright admitting to obstruction of justice in an interview on the record," MSNBC's Chris Hayes tweeted shortly after the interview aired.

Bob Bauer, who was a White House counsel under President Barack Obama, also questioned whether Trump's "demands for reassurance, by their very repetitiveness," implied that Trump "was bringing pressure on the person in charge of a criminal investigation to limit it." In doing so, Bauer said, Trump was obstructing justice.

But Lawfare's experts wrote that "the president's potentially obstructive behavior was not limited to allegedly asking repeatedly whether he was under investigation."

Reports surfaced soon after Comey was fired that Trump had asked for his loyalty more than once: first during a one-on-one dinner in late January, and again earlier this month, days before Comey testified in an open Senate Judiciary Committee hearing.

Comey had not allowed the White House to preview his testimony, which Trump and his aides considered "an act of insubordination," according to Reuters. The New York Times echoed that report, saying Trump was broadly irked by his inability to gain assurances of loyalty from Comey.

Deitz, who said an obstruction-of-justice case would not be easy, said he "personally would be willing to take this case to a jury — especially coupled with [Trump's] supposed demand that Comey be loyal."

Richard Painter, a professor at the University of Minnesota who was President George W. Bush's chief ethics lawyer from 2005 to 2007, told Business Insider on Tuesday that "obstruction of justice would be occurring if there were an express or implied threat to fire" Comey if he didn't drop the Russia probe.

"That's obstruction of justice. The president fired the FBI director," Painter said. "It's all evidence of a major scandal and abuse of power."

'The president has willingly created this self-portrait'

Trump told Holt he was thinking about "the Russia thing" when he fired Comey — specifically about how it was a "made-up story."

"Responsible for the faithful execution of the laws and the integrity of the system of justice, Mr. Trump has chosen to actively dispute the basis for an ongoing FBI investigation that affects his interests," Bauer wrote on Friday.

Louis Seidman, a professor of constitutional law at Georgetown University, said the question of whether Trump would be found guilty by Congress of obstructing justice "is not legal, it is political."

"Has the president violated the oath he took to support and defend the Constitution of the United States? Lawyers and law professors have no special expertise about that," Seidman said. "It's an issue for the American people to decide."

When it comes to examining whether Trump sought to obstruct the FBI's investigation into Russia's election interference and whether the Trump campaign played a role, the president's pattern of behavior and past statements about the probe will likely come back to haunt him. (Trump's comments about barring Muslims from the US were similarly considered when federal courts were debating the intent behind his two controversial executive orders on immigration.)

"What is most remarkable is that the president has willingly created this self-portrait," Bauer wrote. "As scandals in the making go, this one may become famous for featuring the president as the principal witness against himself: he seems committed to uncovering any cover-up."

The Atlantic's Peter Beinart echoed Bauer's assessment, arguing Trump dug his political grave by repeatedly trying to downplay and discredit an ongoing investigation into his campaign.

"As a result of his own ineptitude, Trump is politically weaker than he was on Inauguration Day even though the economy is stronger," Beinart wrote. "And it's harder to mount a populist assault on the rule of law when you're not even that popular."

CNN's Jake Tapper put it simply on Wednesday night: "Every single one of the president's wounds is self-inflicted."