UPDATE 2-Trump pardons former adviser Flynn, who pleaded guilty in Russia probe

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By Jeff Mason and Eric Beech

WASHINGTON, Nov 25 (Reuters) - U.S. President Donald Trump on Wednesday pardoned his former national security adviser Michael Flynn, who had pleaded guilty to lying to the FBI during the investigation into Russian meddling in the 2016 presidential election.

Trump's pardon, which could be the first of several after he lost the 2020 presidential election to Democrat Joe Biden, drew condemnation from Democrats and other critics.

A retired Army general, Flynn pleaded guilty in 2017 to lying to the FBI about interactions he had with Russia's ambassador to the United States in the weeks leading up to Trump's inauguration in January 2017.

He has since sought to withdraw the plea, arguing that prosecutors violated his rights and duped him into a plea agreement. His sentencing has been deferred several times.

"It is my Great Honor to announce that General Michael T. Flynn has been granted a Full Pardon. Congratulations to @GenFlynn and his wonderful family, I know you will now have a truly fantastic Thanksgiving!" Trump wrote on Twitter, a day before the U.S. Thanksgiving holiday.

Trump's move was the highest-profile pardon he has granted since he took office. Among others, the Republican president has pardoned Army personnel accused of war crimes in Afghanistan and Joe Arpaio, a former Arizona sheriff and hardliner against illegal immigration.

"This pardon is undeserved, unprincipled, and one more stain on President Trump's rapidly diminishing legacy," said House of Representatives Judiciary Committee Chairman Jerry Nadler in a statement.

"Donald Trump has abused the pardon power to reward his friends and political allies, and protect those who lie to cover up for him," said House Intelligence Committee chairman Representative Adam Schiff, who led impeachment proceedings against the president.

Flynn served as Trump's first national security adviser but the president fired him after only 24 days for lying to Vice President Mike Pence and as controversy broke over the former general's contacts with then Russian Ambassador Sergei Kislyak.

Flynn was one of several former Trump aides to plead guilty or be convicted at trial in former Special Counsel Robert Mueller's investigation into Moscow's interference in the 2016 U.S. election to boost Trump's candidacy. Russia denied meddling.

The president has spent the days since the Nov. 3 election seeking to overturn the results and refusing to concede to Biden. On Monday, he allowed his administration to take part in a transition to a Biden White House, but he has continued to challenge the election's legitimacy. With less than two months before Inauguration Day, he could focus his remaining time in office on more pardons and other moves to burnish his legacy.

"NOT LEARNED HIS LESSON"

Trump in March said he was strongly considering a full pardon for Flynn. He said the FBI and Justice Department had "destroyed" Flynn's life and that of his family, and cited an unspecified, unsubstantiated report that they had lost records related to Flynn.

Flynn was supposed to help cooperate with the government as part of his plea deal. But he later switched lawyers and tactics, arguing that prosecutors in the case had tricked him into lying about his December 2016 conversations with Kislyak.

The Justice Department has repeatedly denied allegations of prosecutorial misconduct, and U.S. District Court Judge Emmet Sullivan rejected all of Flynn's claims in December 2019.

Federal prosecutors had asked the judge in January to sentence Flynn to up to six months in prison, arguing in a court filing that "the defendant has not learned his lesson. He has behaved as though the law does not apply to him, and as if there are no consequences for his actions."

Flynn also served as head of the Pentagon's Defense Intelligence Agency but was forced out in 2014 in part due to his management style and opinions on how to fight Islamist militancy.

He joined the Trump 2016 election campaign and at the Republican National Convention that year he led supporters in chants of "Lock her up," in reference to Democratic candidate Hillary Clinton.

Other former Trump aides were convicted of federal crimes following the Russia inquiry. Trump's longtime friend and adviser Roger Stone was sentenced on Feb. 20 to three years and four months in prison for obstruction of justice, witness tampering and lying to lawmakers investigating the Russian election interference. Trump commuted his sentence.

Paul Manafort, Trump's former campaign chairman, was sentenced last year to 3-1/2 years in prison after being convicted of unlawful lobbying and witness tampering, which combined with a sentence in a related case equaled a term of more than seven years behind bars. Manafort was released from prison in May and is serving the rest of his sentence at home. (Reporting by Eric Beech and Jeff Mason; additional reporting by Patricia Zengerle, Alexandra Alper and Diane Bartz; Writing by Alistair Bell and Jeff Mason; Editing by Tim Ahmann and Howard Goller)