OK, assume Trump loses and won't leave …

With November fast approaching, here's a recurring question that can't easily be dismissed as alarmist fretting or grim humor: What if President Donald Trump loses his bid for re-election but refuses to concede and instead clings to power? House Speaker Nancy Pelosi expressed this concern last year, saying "we have to inoculate against that." So did Trump's prison-bound former lawyer Michael Cohen. Testifying before Congress, Cohen said, "I fear that if he loses the election in 2020, that there will never be a peaceful transition of power." Even Joe Biden, Trump's Democratic rival, doesn't discount the possibility that Trump would make himself difficult to dislodge, but he suggested that others in government would get the job done: "I promise you, I'm absolutely convinced that they will escort him from the White House with great dispatch."

If Trump does try to hang on to a presidency he's lost, however, he can't actually do very much all by himself. Running the executive branch requires help. Thankfully, there are laws that stop others from using the authorities of the executive branch on behalf of anyone other than the legitimate president. If William Barr, for example, tried to exercise the powers of the attorney general after a Trump loss, he could be subject to criminal prosecution.

The circumstances matter. If Trump legitimately wins on Election Day, he wins — so be it. And if he loses, well, American tradition calls for a peaceful transfer of power to one's successor. But given Trump's rampant tradition-busting, there's more than a little reason to worry that he'll continue to reassert baseless claims that there was election fraud via mail-in ballots or foreign election interference favoring the Democrats, even after he has failed to persuade lawfully constituted authorities of such fantasies. Whatever Trump's excuse, it would require little imagination to suppose that he would claim some need to retain power at least long enough to investigate whatever election irregularity he's claiming, such that, come Jan. 20, 2021, he and Biden would be advancing competing claims to be America's legitimate president.

But while there's a reasonable fear that Trump could take such an appalling and dangerous step, any such effort would have a serious vulnerability. A president cannot run the executive branch alone. We'd like to think that, even if Trump himself refuses to face the music, officials throughout his administration would not follow his lead. And if they were to waver in their commitment to our constitutionally prescribed methods for transferring power, we'd hope they'd be encouraged to do the right thing by virtue of the fact that there are federal statutes that make it unlawful for others to exercise executive branch authorities on behalf of someone who's not actually the president.

For example, it's a crime to pretend to be an officer or employee of the United States when one isn't. A federal statute reads: "Whoever falsely assumes or pretends to be an officer or employee acting under the authority of the United States or any department, agency or officer thereof, and acts as such, or in such pretended character demands or obtains any money, paper, document, or thing of value, shall be fined under this title or imprisoned not more than three years, or both."

Note that the first offense defined by the law involves simply falsely assuming or pretending to be a U.S. officer or employee — there's no demand for money required. So, imagine an outgoing Cabinet member, such as a secretary of defense or homeland security, who's been fired by a legitimate president immediately upon being sworn in on Jan. 20. That outgoing Cabinet member would violate this criminal prohibition if he or she were still to purport to exercise executive branch authority; for example, if the ex-secretary of defense ordered a military operation or ex-homeland security secretary issued an immigration edict, powers that no longer belong to officials ousted from the executive branch.

This would be an extraordinarily risky thing for any outgoing Cabinet official to do — even if they believed the certified election results were wrong. If the outgoing attorney general agreed with the fired Cabinet official, that attorney general would have legitimate authority over federal criminal prosecution only until Jan. 20. After that date, any attempts by the outgoing Cabinet member to exercise official authority would risk criminal prosecution and sentencing by the U.S. attorney for the District of Columbia appointed by President Biden with the new Senate's advice and consent — or by an interim U.S. attorney appointed by Biden before the new Senate could give its consent. Who'd take such a risk?

There are also laws specific to the military that demand obedience to the one and only legitimate president. Under one provision, a chairman of the Joint Chiefs of Staff executing an order given by someone who's not the lawful president could be deemed to have "fail[ed] to do his utmost to prevent and suppress a mutiny or sedition being committed in his presence." That same provision criminalizes even attempting mutiny or sedition. Moreover, another statutory provision criminalizes soliciting or advising the commission of mutiny or sedition.

So, imagine a senior military commander asking those under his or her command to execute an order given by an ousted President Trump: That act could well carry the risk of prosecution for the senior military commander as an attempt at mutiny or sedition. And federal law not only criminalizes certain acts when done on behalf of someone other than the actual president but also criminalizes certain failures to act when so ordered by the lawful president. So, a uniformed service member who disobeys an order from a superior commissioned officer given to him through the proper chain of command — ultimately responsible to the actual president — would also risk criminal prosecution through the military justice system.

Additional laws punish the exercise of other specific executive branch authorities if used for illegitimate purposes, such as in support of someone not actually the legitimate head of the executive branch. For example, there are criminal penalties for intentionally engaging in electronic surveillance under color of law except as actually authorized by federal law. It's thus a crime for someone employed by, say, the National Security Agency or the Federal Bureau of Investigation to engage in electronic surveillance under the pretense of governmental authority without in fact having such authority — and someone claiming to order that surveillance as or on behalf of an illegitimate president would lack the necessary authority.

As we confront a potentially fraught presidential transition ahead, the time to make use of these laws is now. Key Cabinet members affected by them and related statutes — such as Defense Secretary Mark Esper, Chairman of the Joint Chiefs of Staff Mark Milley, Attorney General Barr, Director of National Intelligence John Ratcliffe, FBI Director Christopher Wray, CIA Director Gina Haspel and Acting Secretary of Homeland Security Chad Wolf — will very likely testify before Congress at some point in coming months.

That's an opportunity: A chance, with these Cabinet officials under oath, to ask them whether they are aware of these laws, understand their meaning and significance and intend to abide by them if Trump is determined to have lost the presidency in the Nov. 3 election. Nothing can, with total certainty, ensure a normal transition of power from as abnormal a president as Donald Trump. But it's vital to recognize that, if Trump tries to retain power illegitimately, he'll need help from his Cabinet. Members of that Cabinet should go on the record pledging their ultimate adherence not to Trump but to the Constitution and laws of the United States.

Christopher Fonzone, formerly deputy assistant to the president and National Security Council legal adviser, is a partner at the law firm of Sidley Austin. Joshua A. Geltzer, a former Justice Department and National Security Council lawyer, is executive director and professor of law at Georgetown's Institute for Constitutional Advocacy and Protection. Laurence H. Tribe is Carl M. Loeb University Professor and Professor of Constitutional Law Emeritus at Harvard Law School. They wrote this article for the Washington Post.