I have written this piece for Slate. It begins:

Since the announcement of special counsel Robert Mueller’s decision to not indict President Donald Trump for obstruction of justice or any members of Trump’s family, critics of Trump who still feel some of his actions may have amounted to crimes seem to have put all their eggs in a new basket: the Southern District of New York. These Trump opponents now seem to be hoping that the Justice Department’s branch in the SDNY, which secured a plea deal from Trump’s former personal lawyer Michael Cohen, will come after Trump’s family for financial improprieties and perhaps Trump himself for potential campaign finance violations. But based on what we have learned from the Mueller report, which was released on Thursday, and how it has been handled by Attorney General William Barr, it is time to lower expectations for the SDNY to act, at least as it pertains to the president’s potential criminal liability while in office….

Like the situation with Trump Jr., there might be questions about the president’s willfulness to violate campaign finance laws. Although Trump had tweeted about the similar John Edwards case at the time Edwards was on trial, that might not be enough for prosecutors to conclude that they might be able to prove to a jury beyond a reasonable doubt that Trump knew he was violating the law by making payments to a mistress during a campaign without reporting it. And just as Mueller’s team did not call Trump Jr. to the grand jury, it did not get to personally interview the president or get him before the grand jury. It relied on written answers from Trump, vetted through his lawyers. So it may be very hard to prove willfulness without getting more from the president himself.

And as with the foreign opposition research case against Trump Jr., the hush money payments case against Cohen—and thus Trump—relies upon a contested legal theory. It is true that the Edwards case is precedent for prosecuting this as a crime, but there is a reasonable counterargument that these payments should be treated as personal, and not campaign-related. Cohen might have pleaded guilty to these crimes rather than fight them raising these potential defenses because he was already pleading to other charges and saw no point in contesting these, which allowed him to attack the president as a co-conspirator in a criminal enterprise. At the very least, there is an argument that to avoid the problem of overzealous prosecutors, the better course is to leave criminal prosecutions of politicians in political cases to the most clear-cut cases of criminal liability.