The standard for criminal violations of campaign-finance laws, though, turns on “knowing and willful” violations of those laws. So the president would have had to know that it was illegal, and ordered Cohen to make the payments anyway.

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“It is a big deal that prosecutors concluded that Trump directed Cohen to commit crimes. The one note of caution is that if prosecutors wanted to charge Trump—and we can’t draw any conclusions from this sentencing memo about whether they will—they would also likely have to show that he knew what the laws were, and willfully violated them anyway,” said Brendan Fischer of the Campaign Legal Center. “Demonstrating Trump’s knowledge of anything could be a challenge.”

Fortunately, Trump is here to help. On Monday morning, the president said on Twitter that the payments were “a simple private transaction,” and that it was his “lawyer’s liability if he made a mistake, not me.” If the president took this view of the law at the time he made the payments, he might be guilty of a felony.

“We still don’t know what Trump knew about the law in 2016,” says Fischer. “But Trump and his lawyers should be concerned if Trump’s view of campaign-finance law in 2016 was similar to the view expressed in his 2018 tweet.”

Although the tweet by itself will have little legal impact, it goes to a pattern of deception concerning the president’s conduct. After all, he has lied publicly not only about his alleged affairs and the payments he made to conceal them. He has also lied to the public about his business interests in Russia, he crafted a false account of the Trump Tower meeting in which his son Donald Trump Jr. sought dirt on Hillary Clinton from Russia, and he put forth a false cover story for firing former FBI Director James Comey, saying that Comey was fired for abusing his authority in the Hillary Clinton email investigation.

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“Few defendants admit that they knew they were breaking the law. So prosecutors ordinarily prove the defendant’s state of mind circumstantially, by asking the jury to draw inferences from the defendant’s words and deeds,” said Bruce Green, a law professor at Fordham and a former associate counsel in the investigation of the Iran-Contra affair. “One of the traditional ways of proving intent is through statements or actions that demonstrate ‘consciousness of guilt.’ And one of the traditional ways of showing ‘consciousness of guilt’ is through lies and cover-ups.”

If prosecutors want to convict politicians of bribery or campaign-finance violations, perjury, or obstruction of justice, they need to meet the extraordinarily high burden of showing what the defendant was thinking. But if prosecutors want to, say, charge a person with possession of drugs with intent to distribute, they need only certain circumstantial evidence: A particular quantity of drugs, combined with any number of common household items, such as a scale or plastic sandwich bags, will often suffice for a jury to convict.