When the Supreme Court and lower courts interpret the Constitution and laws, their decrees are public, accessible and subject to debate. In some instances, if an interpretation of the law doesn’t sit well with the public, Congress can respond by amending the law, effectively nullifying a court’s decision. Or if a ruling on a constitutional question is especially egregious, a constitutional amendment, though unlikely, remains an option.

But it turns out there’s a whole category of American law that is above such checks and balances. The public knows nothing about it and there’s no way to challenge it in court, let alone debate it in the halls of Congress.

For decades, the Justice Department’s Office of Legal Counsel has flexed its interpretive power as the ultimate arbiter of what the law is for the executive branch, building a whole body of secret law that remains shielded from public view. Very little is known about these opinions—which carry the force of law, resolve disputes between agencies, direct the conduct of federal officials and can even affect civil rights and liberties. In the view of one scholar, these opinions date “to the beginning of the Republic” and can even “rival the opinions of the Supreme Court.”

These decisions number in the thousands, and the few that become public see the light of day at the discretion of the Justice Department. But the vast majority stay secret—binding executive branch officials and activities across administrations. Because almost everyone who isn’t a lawyer in the office is kept in the dark about these legal conclusions, Congress and the public can’t debate them or seek amendments in the event of abuses. Courts are of no help either.

Indeed, without transparency to test these legal opinions in a court of law or the court of public opinion, it is often the case that the Justice Department has the final say on the actions of federal agencies and officers, and there’s not much anyone can do about it. From Robert Mueller’s decision to follow a 1973 Justice Department recommendation that a president can’t be indicted while in office to numerouspronouncements shielding Donald Trump or officials in his administration from congressional oversight, the Office of Legal Counsel makes law that holds tremendous sway over issues of public concern.

And yet despite the influence of the office’s opinions across the executive branch and their centrality to many of Trump’s controversies, all the public knows about them is the smattering of decisions that are made public from time to time. The Justice Department claims to have the last word over what gets released to the public, subject to a secretive “publication review committee” that calls the shots.

According to one former Justice Department official, in 1991, when Attorney General William Barr first led the Justice Department, the government only published 13 opinions out of an estimated 625 that the Office of Legal Counsel gave to other agencies—a paltry 2 percent that leaves Americans with little understanding of the law that guided the United States’ government at the time.

In 2016, Congress amended the Freedom of Information Act to place a 25-year cap on documents previously shielded by what the Justice Department calls “deliberative process privilege”—which the government has cited in the past to keep Office of Legal Counsel’s precedent-setting legal opinions secret. By law, then, that type of privilege should no longer cover such decisions older than 25 years—though some or portions of them may still be kept from disclosure if, for example, they contain classified information. And neither should the department be allowed to claim attorney-client privilege over these opinions, which aren’t legal advice but controlling decisions of law.

With this understanding of the law and with an eye toward greater transparency, a group of scholars last week filed a lawsuit in federal court arguing that Office of Legal Counsel memoranda that are at least 25 years old should be disclosed to the public under the Freedom of Information Act. Among the plaintiffs are historians of presidential power, the civil rights movement, the laws of war, government surveillance and immigration—all areas where the government’s enormous discretion to enforce the law has been guided by legal judgments that our citizenry would be well served to understand and reckon with, even today. The Justice Department didn’t comply with an earlier administrative request for these opinions.

Understanding past overreach could help us better understand today’s. Barr, then and now, is the kind of attorney general whose expansive views of executive power deserve legal scrutiny—and the public is entitled to know to what extent the Office of Legal Counsel abetted or disregarded his maximalist impulses. More than 25 years ago, he was behind some of the Justice Department’s darkest hours: From a lawless surveillance program he approved that long predated the National Security Agency’s post-9/11 excesses to his role in recommending pardons for officials implicated in the Iran-Contra affair, the American people deserve to know how much secret law he helped create for the presidents he’s served—and how much of it may still be good law for the rest of the executive branch today. For all we know, some of these decisions may have been overruled by later administrations, presidents or attorneys general; the enduring secrecy of these opinions makes it difficult to tell.

Right now, we see these opinions’ weight and opacity playing out. In December, the Trump administration is expected to resume executing federal prisoners on death row, ending a longstanding, de facto moratorium on the federal death penalty. Barr’s decision to reinstate the practice didn’t happen in a vacuum, but was preceded by the advice of the Office of Legal Counsel, which in May concluded in a 26-page memorandum that the Food and Drug Administration lacks the authority to regulate “drugs” and “devices” used in capital punishment.

That conclusion was squarely at odds with the agency’s prior disapproval of pentobarbital, the drug Barr now wants to use in the upcoming executions. Whatever regulatory roadblocks existed before have been removed. The Office of Legal Counsel has now declared what the law is—at least as far as the executive branch and the FDA are concerned. Unless a court steps in, these executions will move forward with Barr’s new lethal cocktail of choice.

The Office of Legal Counsel’s historical memoranda may not all concern issues of life and death, but they should concern all of us—and the Justice Department would be acting in the national interest if it disclosed them as the law requires.