(Bloomberg) -- Former national security adviser Michael Flynn, due to be sentenced for lying to U.S. investigators in the Russia probe, has hired conservative firebrand Sidney Powell as his new legal counsel.

“Attorney Powell is honored to represent General Flynn and he will continue to cooperate with the government in all matters,” her Dallas law firm said in a statement Wednesday.

Powell, who hasn’t yet filed formal notice with the Washington federal court where Flynn’s case is pending, is a former prosecutor who on her website boasts of being lead counsel in more than 500 appellate cases. An advocate of conservative causes on Twitter, including the Flynn saga, she published a book last year titled “Licensed to Lie: Exposing Corruption in the Department of Justice.”

A regular presence on Fox News, Powell has been an outspoken critic of the Enron Task Force prosecutions and has accused prosecutor Andrew Weissmann in particular of overreach. Weissmann was a prominent member of Special Counsel Robert Mueller’s team investigating Russia’s interference in the 2016 presidential election and any obstruction of the probe by President Donald Trump.

More: Michael Flynn Fires His Attorneys Ahead of His Sentencing

Flynn’s decision to hire Powell suggests he might return to the theme he sounded a few months ago, that he was set up by duplicitous FBI agents who had an agenda against the president. U.S. District Judge Emmet Sullivan castigated Flynn for that line of argument in open court in December.

Flynn’s former attorneys told Sullivan last week that they wanted to withdraw from the case because they’d been replaced. Flynn, who pleaded guilty in December 2017, was to be sentenced last December, but the proceeding was put on hold after Sullivan learned that the retired U.S. Army general hadn’t finished cooperating with Mueller’s office and wouldn’t receive the full benefit of having done so.

Flynn’s lead counsel was Covington & Burling LLP partner Robert Kelner.

Flynn served as Trump’s original national security adviser. He lasted just three weeks before being forced out after it came to light that he had lied about conversations he had with Sergey Kislyak, then Russia’s ambassador to the U.S.

“Licensed to Lie reveals the strong-arm, illegal, and unethical tactics used by headline-grabbing federal prosecutors in their narcissistic pursuit of power to the highest halls of our government,” according to a tout on the book’s website. “It’s terrifying -- because it’s true.”

To contact the reporters on this story: Andrew Harris in Washington at aharris16@bloomberg.net;Greg Farrell in New York at gregfarrell@bloomberg.net

To contact the editors responsible for this story: David Glovin at dglovin@bloomberg.net, Peter Jeffrey

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