Trump's lead attorney in the impeachment trial could also be a witness, according to Bolton's book

• The president's lead attorney in the impeachment trial is also a potential witness, according to John Bolton's unpublished book.
• Pat Cipollone, the White House counsel, was reportedly at a meeting in which President Donald Trump asked Bolton to help with his effort to pressure Ukraine into helping him dig up dirt on his political rivals.
• Cipollone is spearheading President Donald Trump's defefense team in the Senate impeachment trial.
• This report raises ethical questions, and House impeachment managers are now demanding Cipollone disclose any firsthand evidence.
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The lead attorney in President Donald Trump's Senate impeachment trial has firsthand knowledge of the effort to pressure Ukraine into digging up dirt on Trump's political rivals, according to former national security adviser John Bolton's forthcoming book.

Pat Cipollone, the White House counsel, has been leading Trump's defense team in the impeachment trial. He could also be a potential witness, according to a report from the New York Times on Friday, which is based on Bolton's unpublished manuscript.

The report states that Trump directly asked Bolton to help with the effort to pressure Ukraine in a meeting that took place more than two months before the president's July 25 phone call with Ukrainian President Volodymyr Zelensky. The phone call sparked a whistleblower complaint that spiraled into an impeachment inquiry and ultimately led Trump to become the third president in US history to be impeached.

During this meeting, Trump reportedly asked Bolton to call Zelensky to ensure he would meet with the president's personal lawyer, Rudy Giuliani, who has been at the center of the impeachment saga and engineered the campaign to urge Ukraine to launch investigations. Bolton did not make the call, the Times said, according to his unpublished memoir.

Cipollone was at this meeting, according to the report, which suggests he witnessed Trump in the action of ordering a top adviser to get involved in the coordinated effort to pressure Ukraine. This raises ethical questions regarding whether it was appropriate for Cipollone to serve as the lead defense for Trump in a trial pertaining to matters the White House counsel reportedly has firsthand knowledge of.

The White House did not immediately respond to a request for comment from Insider.

House impeachment managers are now demanding Cipollone disclose any firsthand evidence. "You may be a material witness to the charges against President Trump, even though you are also his advocate," they wrote in a letter to Cipollone.