Former White House lawyer warns Trump is 'laying the groundwork for an attack on the institution of the Supreme Court'

The former top trial lawyer during the Obama administration unveiled an intriguing -- and alarming -- theory about President Donald Trump's latest attacks on the U.S. Court of Appeals for the 9th Circuit.

Former acting Solicitor General of the United States Neal Katyal unveiled this theory during a Wednesday appearance on MSNBC's "11th Hour" with Brian Williams.

The host played a clip of Trump calling the 9th Circuit "a disgrace" and Chief Justice of the United States snapping back.

Williams put the squabble in the context of special counsel Robert Mueller's investigation into Trump's campaign and administration.

"This back and forth between the titular heads of two of our branches of government comes as the Mueller investigation into this administration is entering, as we like to say, a critical phase," he noted. "More indictments are expected and there is the possibility that Mueller could subpoena Trump to answer questions related to obstruction."

"That could spark a giant legal battle that could very well end up, see how this works, before John Roberts and the other eight justices of the Supreme Court," he added.

Katyal, a professor of national security law at Georgetown University Law Center, then laid out his theory.

"What I fear is going on, unfortunately, is this is not actually about the 9th Circuit," Katyal suggested.

Katyal read a 2012 tweet from Trump, noting that "Trump has criticized John Roberts and criticized other judges all the time."

"We don't have a history of a president attacking the motivations of judges, that's something new and different," he explained. "And I think what's going on here is it's not about the 9th Circuit, it's really about this president's modus operandi, which is to criticize any check and balance on him."

Katyal said, "what I think President Trump is doing right now is laying the groundwork for an attack on the institution of the Supreme Court -- an attack on the institution of an independent judiciary."

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