Rep. Jerry Nadler (D-NY) is pushing the United States Department of Justice to launch an investigation into a former U.S. attorney who vouched for the veracity of claims made by Alexander Smirnov, the informant who was arrested last week on charges of lying to investigators about bribes purportedly paid to President Joe Biden.

In a letter sent to Attorney General Merrick Garland, Nadler questioned how former U.S. Attorney Scott Brady could have vouched for Smirnov's claims when prosecutors found significant problems with his story that they unraveled in a criminal indictment against him.

"Given what we now know about Mr. Smirnov, it seems unlikely that Mr. Brady actually verified any of the information Mr. Smirnov provided to the FBI," Nadler wrote, in a letter flagged by Axios congressional reporter Andrew Solender. "Mr. Brady's testimony to the contrary does not appear to be a mere misstatement -- his comments were deliberative, repeated, and detailed."

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Nadler also cited Smirnov's admission that he got his information about the Bidens from individuals associated with Russian intelligence as particularly damning, and he said that Brady "appears to have been part of a deliberate attempt to launder foreign disinformation through the Department of Justice."

Nadler even linked Brady's actions to former Attorney General Bill Barr and former Deputy Attorney General Jeffrey Rosen, whom he said directed Brady to investigate Hunter Biden's activities in Ukraine.