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Legal experts raised doubts about the value of former President Donald Trump's surprise mystery witness in the Manhattan DA probe after he was revealed to be a former Rudy Giuliani attorney.
Trump on Sunday teased that "the most important witness" was set to appear before the Manhattan grand jury investigating the 2016 hush money payment to adult film star Stormy Daniels. Trump did not name the witness but said it was a "highly respected lawyer who once represented convicted felon, jailbird and serial fake storyteller and liar, Michael Cohen."
Cohen, Trump's former attorney and fixer, pleaded guilty to multiple federal charges in 2018, including campaign finance violations related to the hush money payment — which he said Trump reimbursed him for but the former president's company falsely reported as a legal expense.
The New York Times reported on Sunday that the surprise witness was attorney Robert Costello, who also represented former Trump adviser Steve Bannon. Costello in 2018 was accused of dangling a pardon to Cohen before Cohen decided to cooperate with federal prosecutors, writing in an email to Trump's former fixer that he could "sleep well tonight" because he had "friends in high places."
Cohen ultimately flipped and provided information about Trump's payment to Daniels and his business practices to federal prosecutors and the Manhattan district attorney's office.
The Times reported that Costello and Cohen had a "falling out," and Costello would appear solely to undermine Cohen's credibility if the grand jury votes to hear from him.
Trump on Truth Social claimed that Costello would present "conclusive and irrefutable" evidence.
Former U.S. Attorney Harry Litman noted that Costello had previously represented Cohen.
"He asserts Cohen waived attorney client privilege, permitting him to testify," Litman tweeted. "I haven't seen that confirmed however and Costello's credibility is suspect."
Cohen's personal legal troubles are well-known and it's unclear what Costello could offer the grand jury.
"What Trump's lawyers hope to gain from having Costello attack Michael Cohen's credibility in that forum is a mystery," wrote former Harvard Law Prof. Laurence Tribe.
MSNBC legal analyst Lisa Rubin suggested the move may simply be a delay tactic, noting that Trump over the weekend teased that he would be arrested on Tuesday.
"And then if he is not processed and arraigned Tuesday, they'll point to the delay they caused as purported proof the DA's case is falling apart," Rubin wrote. "There are potential pitfalls with the DA's case. But Costello isn't likely one of them."
The testimony from Costello would come after a request from Trump's lawyers. The Times noted that under state law, a person who is expected to be indicted can request for a witness to appear on their behalf but the decision on whether to hear the testimony will fall on the grand jury.
Costello's appearance would come shortly after Cohen testified before the grand jury, but Cohen would likely be asked to appear as a rebuttal witness if Costello testifies.
The move signals that Trump's legal team is likely to focus on attacking Cohen's credibility because he was convicted of federal crimes but prosecutors could argue that Cohen was acting on Trump's behalf. Trump has repeatedly denied wrongdoing in the case.
Trump over the weekend accused Manhattan DA Alvin Bragg of election interference for targeting a presidential candidate and called on his supporters to protest the looming potential indictment.
"We do not tolerate attempts to intimidate our office or threaten the rule of law in New York," Bragg wrote in a memo to law enforcement in response to the message, according to the Associated Press, adding that his office would coordinate with police to "ensure that any specific or credible threats against the office will be fully investigated and that the proper safeguards are in place so all 1,600 of us have a secure work environment."