WASHINGTON — Even before Rachel Maddow disclosed two pages of President Trump’s 2005 tax returns on her MSNBC program, the White House accused her of complicity in unlawful conduct. “It is totally illegal to steal and publish tax returns,” a statement from the White House said.

The first part of the accusation, about stealing, is true. The second part, about publishing, runs headlong into the First Amendment.

What do we know about how Ms. Maddow obtained the records?

David Cay Johnston, a former tax reporter for The New York Times, said that he received the forms “over the transom,” or unsolicited, in his mailbox.

Did whoever sent the documents to Mr. Johnston commit a crime?

Perhaps. A federal law makes it a felony for federal or state employees “willfully to disclose to any person” without authorization “any return or return information.” The First Amendment would provide no defense to a source who violated such a law.