This Trump lawyer will be the most 'sharply incriminating' witness against his boss: Former prosecutor
Jack Smith, Donald Trump (Smith photo by Robin Van Lonkhuijsen for AFP/ Trump by Saul Loeb for AFP)

Former Donald Trump attorney Evan Corcoran is set to testify to a grand jury empaneled by Justice Department special counsel Jack Smith in the Mar-a-Lago classified documents investigation. This comes after Smith secured a ruling from a federal judge ordering Corcoran, who is accused of misleading investigators, to turn over documents, creating an exception to usual attorney-client privilege.

On MSNBC Thursday, former federal prosecutor Glenn Kirschner explained what could make this such a bad situation for the former president.

"Let me turn to Jack Smith's other investigation," said anchor Ayman Mohyeldin. "The former president's attorneys expected to testify before the grand jury as soon as, I guess tomorrow, in the Mar-a-Lago documents case. What do you make of that? Why is that significant?"

"You know, it's hugely consequential," said Kirschner. "We don't often have criminal defense attorneys testify about the clients' crimes, except when the crime-fraud exception applies, which causes the attorney-client privilege to evaporate."

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"I think the most interesting thing now moving forward is whether Evan Corcoran will plead the Fifth Amendment, will invoke his own Fifth Amendment right against self-incrimination, because he believes he was complicit in Donald Trump's crimes, or if he believes that he was an unwitting dupe, Donald Trump was giving him false information and he was simply certifying it and passing it on to the federal government."

If it's the latter, Kirschner then, "his truthful testimony would not incriminate him."

"He'd have no reason to plead the Fifth and he can testify and, frankly, become one of the most sharply incriminating witnesses against his former client Donald Trump" said Kirschner. "So even though the grand jury proceedings are secret, so we may not know these things right away, I suspect we'll know them before too long."

Watch video below or at this link.

Glenn Kirschner says Corcoran could incriminate Trump