Acting Defense Secretary Christopher Miller — and every civilian and sworn member of the U.S. military under Miller’s chain-of-command — has a legal duty, under the Uniform Code of Military Justice, to refuse to carry out an unlawful order to take part in a military coup that is designed to prevent the peaceful transfer of power to the duly elected 46th President of the United States on January 20, 2021. That duty holds even if the order to carry out that military coup is issued by the current Commander in Chief.

This is not an abstract concern.

Recall that the increasingly desperate Donald Trump previously discussed with the disgraced and recently pardoned, former National Security Advisor, Lt. General Michael Flynn, the possibility of utilizing the military to facilitate a re-do of what U.C. Irvine Law Professor Rick Hasen described as a “decisive” electoral victory for his opponent, Joseph R. Biden.

The prospect that Trump would dare to issue an unlawful coup order was driven home by the fact that all ten living former Secretaries of Defense found it necessary to publish an ominous Washington Post editorial on Sunday that they directed to Miller. With his subordinates, Miller has failed to fully cooperate with the transition, according to President Elect Biden.

The former Secretaries of Defense not only admonished Donald Trump’s newly placed Acting Secretary of Defense that he had a duty to facilitate the transition, but also issued a stark warning: “Civilian or military officials who carry out [efforts to involve the U.S. military in the election] would be accountable, including facing criminal penalties, for the grave consequence of their actions on our republic.”

The potential for such an unlawful order is underscored by the fact that the former Secretaries of Defense, who signed off on the op-ed, included Mark Esper. He was fired by Presidential Tweet on November 9 — two days after the networks called the election for Biden. While we don’t know precisely what Trump may have conveyed to Esper, there can be no doubt but that Esper, more than any other former Secretary of Defense, is acutely aware of Trump’s post-election state of mind.

The word needs to go out, not only to Miller’s subordinates and to high-ranking members of the military, serving at the Pentagon, but also to everyone who wears the uniform. You must not obey an unlawful order to carry out a military coup.