‘Really bad day for the president’: Ex-prosecutor reveals why judge’s new ruling is devastating for Trump

President Donald Trump suffered a damning legal setback on Monday, a career former prosecutor explained on MSNBC.

U.S. District Court Judge Amit Mehta ruled against Trump with a blistering decision on Monday.

Former Assistant U.S. Attorney Glenn Kirschner was interviewed by MSNBC's Lawrence O'Donnell on "The Last Word."

"Glenn Kirschner, you were in the courtroom when this case was argued and here you have an opinion by the judge in your hands today saying he actually didn’t hear any serious issues raised by President Trump’s lawyer," the host noted.

"When I sat in that courtroom, I was shaking my head because I heard the president’s lawyer William Consovoy say things like Congress can’t investigate a president who violates criminal statutes and Congress can’t investigate a president who violates the Constitution, for example, the emoluments clause and Congress can’t investigate a president who may have a financial interest, a conflict of interest in legislation he supports or executive orders he authors," Kirschner explained.

"And Judge Mehta was shaking his head," he recalled. "He was being polite, but you could see he was buying into none of it. So when I see him use a word like your arguments were unfathomable, I was fully expecting this kind of an opinion to be handed down."

However, there was one part of the opinion which surprised Kirschner.

"What I wasn’t expecting necessarily, Lawrence is that it would be handed down so quickly. Let me tell you, after 30 years in courts -- including decades in the courts of Washington, D.C. -- rarely do things happen quickly, but the fact that Judge Mehta handed down this decision in six days is pretty remarkable," he noted.

"I do think the sort of dam is breaking at this point. And this is a great day for transparency and for accountability, but a really bad day for the president's seemingly endless attempts to cover up his own misconduct," he concluded.

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