WASHINGTON – Even before Rachel Maddow disclosed two pages of President Donald 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.

Q: What do we know about how Maddow obtained the records?

A: 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.

Q: Did whoever sent the documents to Johnston commit a crime?

A: 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.

But Johnston, without providing evidence, said the leak may have been authorized. "It's entirely possible that Donald sent this to me," he said on Maddow's show. "It's a possibility, and it could have been leaked by someone at his direction."

Q: Is it illegal for journalists to publish tax information received unsolicited?

A: The same federal statute says yes. But the statute is almost certainly unconstitutional. "It shall be unlawful for any person to whom any return or return information" is disclosed without authorization, the law says, "thereafter willfully to print or publish in any manner not provided by law any such return or return information." But the Supreme Court has said that journalists are free to publish truthful information on matters of public concern notwithstanding laws to the contrary as long as they did nothing illegal in obtaining the information.

Q: What does the leading Supreme Court case say?

A: In 2001, in Bartnicki vs. Vopper, the Supreme Court considered whether a Pennsylvania radio station had been entitled to air a surreptitious recording of a cellphone conversation. A federal law made it illegal to broadcast such recordings, but the radio station aired it anyway.

The recording had arrived unsolicited. Its contents, about a labor negotiation, were truthful and newsworthy.

Even though the station's source obtained and disclosed the information unlawfully, the radio station was free to broadcast it because it was "a matter of public concern," Justice John Paul Stevens wrote for the majority. "A stranger's illegal conduct does not suffice to remove the First Amendment shield from speech about a matter of public concern," Stevens wrote.

Q: Are Trump's tax returns "a matter of public concern"?

A: In a concurring opinion in the Bartnicki case, Justice Stephen Breyer said that it mattered that the union officials were minor league public figures. "They thereby subjected themselves to somewhat greater public scrutiny," he wrote, "and had a lesser interest in privacy than an individual engaged in purely private affairs."

The president of the United States, it would follow, invites much more probing public scrutiny.