President Donald Trump speaks to reporters on the South Lawn of the White House in Washington, Dec. 4, 2017, before heading to Utah.
President Donald Trump speaks to reporters on the South Lawn of the White House in Washington, Dec. 4, 2017, before heading to Utah.

WHITE HOUSE - U.S. President Donald Trump said Monday his former National Security Adviser Michael Flynn has been treated unfairly by investigators looking into Russia’s influence on the 2016 presidential election.

"I feel badly for General Flynn. I feel very badly," Trump told reporters. "He’s led a very strong life. And I feel very badly."

Flynn pleaded guilty Friday to lying to the Federal Bureau of Investigation last January about his contacts with Russia’s ambassador to the United States. The conversations came weeks before Trump’s inauguration.

The president compared Flynn’s lies to the FBI with comments made by his presidential rival Hillary Clinton when federal investigators asked about her use of a private email server during her time as secretary of state.

"Hillary Clinton lied many times to the FBI. Nothing happened to her. Flynn lied and they destroyed his life. I think it’s a shame," Trump said Monday as he departed the White House on a trip to Utah.

The president noted Clinton was not under oath when she spoke to the FBI, while Flynn was.

FILE - Republican presidential nominee Donald Trum
FILE - Republican presidential nominee Donald Trump listens to Democratic presidential nominee Hillary Clinton during the second presidential debate at Washington University in St. Louis, Oct. 9, 2016.

Former FBI director James Comey testified in July 2016 that Clinton did not lie to FBI agents investigating her emails.

"We have no basis to conclude she lied to the FBI," Comey told House Oversight Committee during an open hearing.

Trump’s comments come as legal experts and investigators are parsing a tweet that appeared over the weekend on his Twitter account.

Trump tweeted that he "had to fire General Flynn because he lied to the Vice President and the FBI. He has pled guilty to those lies. It is a shame because his actions during the transition were lawful. There was nothing to hide!"

That suggests the president was aware that when he fired Flynn on February 13 -- after less than a month as his national security adviser -- he knew that the former director of the Defense Intelligence Agency had lied to the FBI when agents interviewed him weeks earlier.

The president’s personal lawyer John Dowd told the Axios news website that he had written the tweet himself. Dowd called it "my mistake," saying he had drafted it and passed it to White House social media director Dan Scavino, who then posted it to the @realdonaldtrump account.

The tweet has led to intense scrutiny about whether the president knew when he fired Flynn that his aide had lied to the FBI, which could be construed as an admission that he obstructed justice when he asked former FBI director James Comey to end his investigation of Flynn, and then later fired Comey.

The ranking Democrat on the Senate Judiciary Committee said Sunday that Special Counsel Robert Mueller is formulating a case of obstruction of justice against the president as he moves forward with his investigation into Russian election meddling

FILE : Special Counsel Robert Mueller (R) departs
FILE : Special Counsel Robert Mueller (R) departs after briefing members of the U.S. Senate on his investigation into potential collusion between Russia and the Trump campaign on Capitol Hill in Washington, U.S., June 21, 2017.

"I think we see this in the indictments, the four indictments and pleas that have just taken place, and some of the comments that are being made. I see it in the hyper-frenetic attitude of the White House: the comments every day, the continual tweets," said Senator Dianne Feinstein on NBC’s "Meet the Press."

"And I see it, most importantly, in what happened with the firing of Director Comey and it is my belief that that is directly because he did not agree to lift the cloud of the Russia investigation," according to Feinstein. "That’s obstruction of justice."

Several Trump defenders have dismissed the possibility of any obstruction of justice charge against the president, saying the president was within his constitutional rights in talking to and subsequently firing Comey.

The "president cannot obstruct justice because he is the chief law enforcement officer under [the Constitution's Article II] and has every right to express his view of any case," presidential attorney Dowd told Axios.

Former Harvard law professor Alan Dershowitz agreed. "You cannot charge a president with obstruction of justice for exercising his constitutional power to fire Comey and his constitutional authority to tell the Justice Department who to investigate and who not to investigate," Dershowitz said in comments to Fox News.

Former U.S. National Security Adviser Michael Flyn
Former U.S. National Security Adviser Michael Flynn departs U.S. District Court, where he was expected to plead guilty to lying to the FBI about his contacts with Russia's ambassador to the United States, in Washington, Dec. 1, 2017.

Many other legal analysts, however, argue that the president's tweet is a clear admission that he was trying to alter the course of the investigation at a time when he was aware that Flynn had lied under oath.

Ned Price, who was a special assistant to President Barack Obama on the National Security Council staff, questioned whether Trump’s seemingly incriminating tweet could have been written by someone else. "It seems as implausible as it is convenient to President Trump," Price told VOA.

"The idea that a lawyer would draft that – without any input from or clearance by Trump – doesn't strike me as believable," said Price, a former CIA senior analyst and spokesperson. "Add that to the long list of cover-ups."

Republican Senator Susan Collins, speaking to "Meet the Press" on Sunday, said the president should not be commenting on the case at all. "The president should have no comment whatsoever on either of these investigations," Collins said. "And the only thing that he should be doing is directing all of his staff and associates to fully cooperate."