‘The president ought to be scared’: Ex-DOJ official says Mueller has ‘oodles’ of evidence against Cohen and Trump

President Donald Trump has legitimate concerns about the legal exposure he is facing, former top Department of Justice official Chuck Rosenberg explained Tuesday on MSNBC's "Deadline: White House" with Nicolle Wallace.

"Against the backdrop of Donald Trump's escalating war of words against the late John McCain (R-AZ) -- stop it for a second, and let that sink in -- Donald Trump today confronted with new reporting that Robert Mueller's investigators began investigating the Trump Organization's ties to Russia just months after Trump was sworn-in as president," Wallace reported.

"Hundreds of pages of court documents unsealed today in the Michael Cohen case -- giving us a rare peek inside the investigation's earliest phase and offering us tea leaves about what that part of the investigation yielded and what drove the decision to send other Cohen cases to the Southern District of New York where the president has already been identified as Individual One in Michael Cohen's sentencing memo, and is widely believed to face ongoing legal exposure," she explained.

Rosenberg explained the legal standard of probable cause that was required to be met in order for the search warrant to be issued.

"Here we have pages and pages and facts after facts which detail the probable cause that the government had to search Michael Cohen's home, his hotel room, and his office," Rosenberg noted.

"The Fourth Amendment to the Constitution requires that the government have probable cause to search your home, your business, your office, he continued. "Probable cause is the lowest standard in the criminal law, if we want to convict someone at trial, it's proof beyond a reasonable doubt. If we want to detain them pending trial, it's clear and convincing evidence. But the Fourth Amendment to the Constitution only requires probable cause -- and this is not a technical term -- but they had oodles of probable cause."

"It's just remarkable how much stuff they had and how precisely they laid it out in their affidavits for their warrants, and so the president ought to be scared," he continued. "I understand his reaction. I don't condone it, but I understand it."

"There's a lot of stuff that they have and it seems like in part they're coming after Individual One -- the president of the United States," he added.

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