A binder of highly classified intelligence about Russia's interference in the 2016 presidential election, last seen with former President Donald Trump, has gone missing, and no one seems to know where it is — coinciding with a moment when the former president is being prosecuted for retaining national defense information at his Mar-a-Lago country club.

All this smells rotten, argued former prosecutor Kristy Greenberg on MSNBC's "The Beat" Friday evening — and it could lead to criminal charges.

"So Kristy, [former FBI official] Frank [Figliuzzi] has talked a bit about accountability, like reforming the entire system for dealing with classified information. But accountability could also take more mundane forms like legal liability or criminal liability," said the host. "Is there perhaps criminal liability for whoever took this binder, whether it was Mark Meadows in the Oval Office with a candlestick, or someone else?"

"Certainly," confirmed Greenberg. "There are a lot of questions. What information in the binder that was received by someone else or that's missing? How much of that was still classified? Was any of that declassified? Whoever was gaining access to it, what security clearance did that person have, if any? And then as to the content, if it was classified or unclassified, regardless, was there national defense information in there? Willful retention of national defense information, as we know from the Mar-a-Lago case, that's a felony."

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"So there are a lot of questions," Greenberg continued. "But when you're dealing with this kind of sensitive material, classified or not, this is the kind of material that you would expect to be guarded closely. And Cassidy Hutchinson saying there was a safe where this had to be, and Mark Meadows saying, keep it in your drawer. No, there need to be procedures for how to deal with highly sensitive information."

"The idea that this was being given out and copied potentially to journalists and to others on the Hill — nobody knows how many copies there were or where it went — this all just seems like a real mess when you're talking about national security secrets," added Greenberg. "As you said, assets. Real people who are confidential sources. Investigative methods. Figuring out how it is the FBI is getting the information. Information we're getting from other countries. Our relationships. I mean, it's a legal problem, but it's also just a huge diplomatic mess as well."

Watch the video below or at the link.

Kristy Greenberg on the missing Russia binderwww.youtube.com