Importantly, Weissmann, who made his remarks on MSNBC Thursday, notes that the document in question, if it is as described, contains "war plans."
"And the proof that we have learned just publicly is so strong. And Jack Smith is such a competent and aggressive prosecutor. It is inconceivable to me that this would not be charged, and having a tape recording of the prospective defendant admitting his possession of a classified document that he had no right to have," Weissmann says.
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"And not just any classified document. I think it's really important to remember that what he talks about reportedly, is a classified document involving something that is unbelievably sensitive, which is war plans of the United States against another country."
Where news broke Wednesday NYU Law professor of law Ryan Goodman, a former U.S. Dept. of Defense Special Counsel, wrote: “War plans are among the most highly classified documents. Puts pressure on DOJ to indict, and a jury to convict.”
Some say, based on the audio, Trump might have been holding the document as he was being recorded at his Bedminster, New Jersey golf resort, allegedly discussing it.
“Make no mistake. This is squarely an Espionage Act case,” Goodman also said, calling the news a “bombshell.”
Explaining the gravity of the document, Weissmann notes, "this is not just taking love letters of Kim Jong Un or salacious material about the president in France. This is exactly what the Department of Justice and the intelligence community is worried about."
Continuing to explain just how serious this is, Weissmann served up the ground rules.
"Let's remember government documents, whether classified or not, belong to the government. They are not to be retained by a private citizen. And the former president is a private citizen. So for instance, when I was in the Department of Justice, the number of documents I could take when I left the Department of Justice would be zero. So you're not supposed to have that possession of government documents. If they are classified, there can be an additional type of charge, but it's not required that that material be classified or classified at a particular level."
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"What you're looking at here is whether the person either knowingly took the documents or knowingly retained the documents. Important this tape recording, if it exists, as recorded, is that you've got Donald Trump admitting that he has in his possession a classified document – doesn't matter if it's Secret, Top Secret, it's classified, that itself is a crime."
And then finally, with respect to dissemination, the recording is that there does appear to be at least some dissemination of the information because Donald Trump, although he doesn't turn the document over or quote from it, he does talk about what is in there. In other words, the reason we're all talking about the fact that involves war plans involving Iran is because reportedly that is what Donald Trump said was in the document. If that proves out, that is a form of dissemination."
On social media later Thursday, Weissman tweeted, "Days, not months..." suggesting he believes an indictment of Trump would be coming sooner rather than later.
Watch Weissmann below or at this link.