Here's how Mueller can prove Don Jr. committed perjury about the Trump Tower meeting: former federal prosecutors
Special counsel Robert Mueller on CNN (screen capture)

With increasing indications that special counsel Robert Mueller plans to bring more charges, a former federal prosecutor explained Monday how he could prove Donald Trump's aides lied either to investigators or to Congress.

John Flannery, a former New York federal prosecutor, told MSNBC that if Mueller were to try to prove Donald Trump Jr. lied about the infamous Trump Tower meeting with Russians who claimed to have "dirt" on Hillary Clinton in 2016, he would do so by comparing statements and documents.

"The best way is you get as much testimony as you can in statements of what people say, and you look at the inconsistencies," Flannery said. "And you look at how that compares to documents, how that compares to the testimony of others -- documents are good -- how it compares with tape recordings, for example, and then you judge that if a person is making a false statement you can contradict, it's that evidence of consciousness of guilt."

Mueller would then have to determine what the person's motive would be and what they're hiding, the former prosecutor said.

In the case of former Trump "fixer" Michael Cohen, Flannery added, prosecutors did "everything they could to corroborate him, and they've said so with witnesses and tapes and exhibits and documents and evidence."

Mueller, he mused, has "done this his whole life" and is likely more experienced than most prosecutors in America.

"I think his dream team sometime in the next several weeks may do Roger Stone," he said. "We might see Don Jr. We might see a whole series of people in the hot seat. And I think that's what we're looking for."

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