When Bernie Sanders told Hillary Clinton in their first debate back in October that he was “sick and tired of hearing about your damn e-mails,” he spoke for most of us. Yet she continues to be vulnerable on this issue: While the FBI recently recommended no charges in the matter, FBI Director James Comey took the opportunity to rebuke Clinton for her decision to maintain private e-mail servers, which led to a drop in the polls. That’s why Republicans are doing everything they can to keep her e-mail in the news. And now they have a new front in their campaign: They’re arguing that Clinton violated the Freedom of Information Act (FOIA) by storing official information on her private e-mail servers. Anti-Clinton legal activists have brought a lawsuit in US District Court for the District of Columbia based on a potential FOIA violation, and the FBI’s decision did not resolve that question—so expect to hear lots more about Clinton’s e-mails between now and November.

The Freedom of Information Act has historically been a powerful weapon against government secrecy. Government officials everywhere, including Hillary Clinton, have always liked secrecy; by keeping the public from learning what they have done, government officials hope to avoid criticism, hinder the opposition, and stay in power. But democracy in America is not powerless before this practice. FOIA requires that officials give the information in their files to “any person” who requests it—unless it falls into a small number of exempt categories, including “national security.” Journalists and historians have relied on the FOIA for several decades to do their work, exposing official lying, corruption, and cover-ups. (I’ve been one of them: I sued the FBI for their Nixon-era files on John Lennon, challenging their claim that releasing parts of the file would endanger “national security.” When the files were eventually released, they didn’t involve national security, but they did document White House abuse of power in ordering Lennon’s deportation from the United States as the 1972 election was approaching in an effort to silence him as a critic of Nixon’s.)

There’s one big problem, however, with the FOIA: It applies only to documents in the files of federal agencies—and that’s why Clinton’s setting up private servers creates a conflict with the freedom-of-information law. Officials long ago figured out that they could avoid disclosing the records of their actions by moving records outside of government-agency control. The most notorious has been Henry Kissinger. Of course, in his day as secretary of state there was no e-mail; instead, there were telephone records. When he left Washington, Kissinger prevented disclosure of his phone records under the FOIA by removing them from the State Department and donating them to the Library of Congress, which is not a “federal agency,” and which agreed that, for a long time to come, those records would be made public only with the consent of the other parties to the calls. The Reporters’ Committee for Freedom of the Press challenged the agreement by filing a FOIA lawsuit for the documents. The Supreme Court eventually ruled that, since the records were no longer at the State Department, it didn’t have to comply; and, since the Library of Congress is officially part of Congress, it didn’t have to comply either, because the FOIA doesn’t cover Congress.