"It shall be unlawful for any person to whom any return or return information (as defined in section 6103(b)) is disclosed in a manner unauthorized by this title thereafter willfully to print or publish in any manner not provided by law any such return or return information. Any violation of this paragraph shall be a felony punishable by a fine in any amount not exceeding $5,000, or imprisonment of not more than 5 years, or both, together with the costs of prosecution."
The law further states that the term "return information" covers not only return documents themselves but also the "amount of his income, payments, receipts, deductions, exemptions, credits, assets, liabilities, net worth, tax liability, tax withheld, deficiencies, overassessments or tax payments."
Understanding that there could be at least some legal risk attendant to publication of Trump's tax returns, New York Times executive editor Dean Baquet and Washington Post associate editor Bob Woodward said at Harvard in September that they would be willing to do jail time, if that were the price to pay.
In October, the Times published the first page of Trump's 1995 New York state resident income tax return, the first page of his New Jersey nonresident tax return and the first page of his Connecticut nonresident tax return. Like Johnston did Tuesday, Times reporter Susanne Craig said at the time that she found the tax documents in her mailbox.
After the Times published its story, the legal blog Concurring Opinions collected the views of 10 experts in First Amendment law, who concluded that the newspaper was likely on firm ground, so long as it did not participate in illegally accessing Trump's tax documents. The same applies to Maddow and Johnston now.
One other indication that Maddow and Johnston are probably in the clear: Trump, through an attorney, threatened "prompt initiation of appropriate legal action" against the Times last fall but never followed through.