What about her emails?

Donald Trump raised that question like a red flag for three years, as candidate and president, casting doubts on how Hillary Clinton used a private email server to communicate with her staff and others while she was secretary of state.

“Hillary set up an illegal server for the obvious purpose of shielding her criminal conduct from public disclosure and exposure, knowing full well that her actions put our national security at risk,” Mr. Trump said late in the campaign.

“Lock her up!” the crowds still chant at his rallies.

Now a three-year State Department investigation has found that, while about three dozen people violated protocols about classified material, they “did their best to implement them in their operations” and “there was no persuasive evidence of systemic, deliberate mishandling of classified information.”

This comes after the F.B.I. determined months before the election that, while Mrs. Clinton was “extremely careless” in having used a private email server for government communications, she did nothing illegal.

Federal employees are supposed to conduct business on government networks to keep communications secure from foreign adversaries and to create a record of how the American government carried out its affairs. Those records let current officials (and also future historians) understand why actions were taken and make informed decisions.

Despite Mr. Trump’s professed concern about the integrity of government communications, his administration doesn’t seem to take it too seriously.

Ivanka Trump and her husband, Jared Kushner, top White House advisers, used the messaging service WhatsApp for official — possibly classified — White House business, potentially violating federal records laws, according to congressional investigators. For example, Mr. Kushner may have used it to communicate with Crown Prince Mohammed bin Salman of Saudi Arabia, who the C.I.A. says ordered the murder of the journalist Jamal Khashoggi. Both Ms. Trump and Mr. Kushner also used private email accounts for official business, according to their lawyer.

They were not the only ones. Betsy DeVos, the education secretary, used a personal email account for some government business, her department’s inspector general found. White House officials told The Times in 2017 that Stephen Bannon, the former chief White House strategist; Reince Priebus, the former chief of staff; Gary D. Cohn, the former economic adviser; and Stephen Miller, a top aide, all had used personal email accounts for government business, as did K.T. McFarland, the former deputy national security adviser.

The keeping and preservation of records isn’t just a matter of concern for historians, it is essential to the smooth functioning of the government. When government officials do business outside official channels, it not only hampers the business of governing, it also raises the concern that there is something to hide. A State Department investigation in 2016 found that other secretaries of state had handled classified information on unclassified email systems. While Mrs. Clinton’s name will always be associated with the practice, it is disappointing to see the use of personal email accounts proliferate across the government.

So the Trump administration’s widespread use of personal accounts for government work raises the unavoidable question: What about those emails?