The publisher of Michael Wolff’s explosive exposé on the Trump White House has called the President’s attempt to stop publication of the book “unconstitutional.”

In an email to all employees on Monday morning, Macmillan CEO John Sargent recapped the timing of last week’s demand from President Trump that the publisher cancel its plans to put out Michael Wolff’s Fire and Fury. Instead, Macmillan pushed up publication to the following day, four days earlier than initially planned. The book has since gone on to top bestseller charts, selling out at many retailers.

Sargent wrote to his staff to emphasize the importance of the decision to move ahead with publication. “The President is free to call news ‘fake’ and to blast the media,” he wrote. “That goes against convention, but it is not unconstitutional. But a demand to cease and desist publication — a clear effort by the President of the United States to intimidate a publisher into halting publication of an important book on the workings of the government — is an attempt to achieve what is called prior restraint. That is something that no American court would order as it is flagrantly unconstitutional.”

Sargent went on to detail Supreme Court cases that support his argument, including the Pentagon Papers case, in which Justice Hugo Black wrote, “The press was to serve the governed, not the governors. The Government’s power to censor the press was abolished so that the press would remain forever free to censure the Government.”

“We will not allow any President to achieve by intimidation what our Constitution precludes him or her from achieving in court,” Sargent wrote. “We need to respond strongly for Michael Wolff and his book, but also for all authors and all their books, now and in the future. And as citizens we must demand that President Trump understand and abide by the First Amendment of our Constitution.”

Later in the day, Macmillan’s Henry Holt imprint made its response with a lawyer’s letter to Trump’s attorney. On behalf of Holt, Elizabeth A. McNamara (a partner at Davis Write Tremaine, and, incidentally, counsel for Simon & Schuster in its Milo Yiannopoulos lawsuit) notes that the original letter “broadly challenges” Fire and Fury with containing “false/baseless claims,” but “stops short of identifying a single statement in the book that is factually false or defamatory.”

“Instead,” she continues, “the letter appears to be designed to silence legitimate criticism. This is the antithesis of an actionable libel claim.”

Responding to a request by Trump’s lawyer that Holt and Wolff retain all documents relating to the book, McNamara writes that the publisher and author will comply with the law’s obligations — and requests that the Trump administration do the same. “Should you pursue litigation against Henry Holt or Mr. Wolff, we are quite confident that documents related to the contents of the book in the possession of President Trump, his family members, his businesses, his campaign, and his administration will prove particularly relevant to our defense.”

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