Attorney General William Barr announced last week a new Justice Department policy to prevent "overreach" by governors and other local authorities seeking to contain the coronavirus pandemic. The department, he wrote in a memo to U.S. attorneys across the country, will "monitor state and local policies and, if necessary, take action to correct them." Earlier, on Fox News, Barr expressed his own views on the matter: "I think we have to allow people to adapt more than we have, and not just tell people to go home and hide under their bed."

Several federal judges agree. In a decision issued the day before Easter, U.S. District Judge Justin Walker blocked, on First Amendment grounds, a supposed prohibition on Easter services that, he said, had been issued by the mayor of Louisville — though it was not clear that the mayor had done more than strongly discourage public gatherings. On Saturday, the Sixth Circuit Court of Appeals similarly held that an order prohibiting mass gatherings in Kentucky could not be applied to a church service that adhered to social-distancing guidelines.

Aggressive interventions by the federal government and courts in states' efforts to manage the pandemic are a dangerous but predictable development in these polarized times. While most civil liberties lawsuits against state stay-at-home orders have failed, there are sure to be more in the coming months. And when states reissue those orders to contain local outbreaks and the predicted second wave of contagion in the fall, courts will again be called on to evaluate the age-old conflict between civil liberties and public safety.

There are powerful reasons, however, for courts to stay out of emergency public health matters. Chief among them is a little-understood asymmetry in the way our judicial system responds to complaints about government misbehavior. When the government issues orders that restrict liberties, our constitutional tradition allows affected people to ask judges to block those orders. But when the government fails to issue orders, when it underreaches rather than overreaches, citizens have no right to judicial review. Courts do not recognize a constitutional right to health or safety; they do not allow people to sue for orders compelling the government to act.

Thus, while gun owners, churchgoers and property owners can challenge overzealous stay-at-home orders, the elderly, the immune-suppressed and the rest of us have no legal recourse when government fails to protect us. Governors who choose not to impose adequate precautions, for political reasons unrelated to public health, are free to do so.

This is not merely a theoretical issue. The Louisville and Sixth Circuit cases are only two of several that involve challenges to restrictive orders on religious grounds. In addition, judges have reviewed stay-at-home orders that allegedly violated constitutional rights to speech and assembly (by shutting the campaign office of a state legislative candidate), gun possession (by forcing firearms stores to close) and property (by requiring other businesses to shut down), among other rights. (In one case, a court ruled that the closing of a gun range violated the Second Amendment.) Even when ruling for the government, courts have frequently suggested that in the future they will be less willing to uphold strict stay-at-home orders. In the midst of a public health crisis and extreme uncertainty about how the virus works, the burden on governments is great.

The result is one-sided pressure on governors — and a constitutional system that works like a ratchet: Every judicial opinion that restricts stay-at-home orders stays on the books as a constraint on the government's response to public health emergencies, and no judicial orders push in the other direction. This creates headwinds for governors who seek stringent measures to protect public health, and tailwinds for governors, most notoriously Brian Kemp, R-Ga., who are rushing to reopen for business.

This asymmetry is baked into the American constitutional system and has been most evident during national security emergencies. It has been justified on two grounds: first, that Americans frequently panic when confronted with a new threat, and the government responds by overreacting. The standard parade of examples includes Abraham Lincoln's suspension of habeas corpus at the start of the Civil War, the crackdown on political dissent during World War I (and later wars) and the anti-communist hysteria of the 1950s. Often, innocent minorities are the victims of this overreaction.

Second, many people believe that whenever the government obtains new powers to counter a threat, it retains those powers long after the threat has receded. The result is an "imperial" presidency and a government with an ever-growing ability to surveil, detain and make war.

This civil-libertarian historical narrative contains more than a grain of truth, though it tends to be accepted on faith rather than rigorously analyzed. Americans have often underreacted to threats, too, as they did with the rise of Hitler before World War II, hampering Franklin Roosevelt's efforts to prepare for the conflict. And many powers the government has acquired during wartime have been retained because they are necessary to protect the country from another war. (The Office of Strategic Services, the predecessor to the CIA, was created by presidential military order during World War II.)

But whether you agree or disagree with the civil-libertarian view, its underlying assumptions do not hold up well in the face of the coronavirus pandemic. In this case, the problem has been government inaction, not overzealousness. President Donald Trump dragged his feet despite the mounting death toll; federal officials failed to provide states with the tests necessary to track the spread of the virus, among other lapses. Many governors refused to impose needed public safety measures or have lifted them too soon. There is no evidence that the president or any governor is using the pandemic as an excuse for amassing power.

Minority groups — including African-Americans and Hispanics — have more to fear from the pandemic than from discriminatory government lockdown orders. Nor has the public overreacted to the pandemic in the way civil libertarians might have predicted: To the contrary, through March, at least, the public did not fear it enough.

The coronavirus pandemic poses exquisitely difficult questions for politicians and public health authorities. Because of the explosive rate of contagion, extremely severe restrictions on liberty may be justified even before a single death has occurred. At the same time, politicians must take into account people's willingness to follow such orders, the limits of police enforcement, the extraordinary uncertainties about how the virus behaves and how the illness can be treated, and the economic harm that results when people are forced to stay at home.

These actions do not benefit from judicial second-guessing. Courts are not public health experts, and in the midst of an emergency, they are in no position to hold hearings so that public health officials can testify, lawyers can cross-examine them and other fact-finding steps can be taken (as is normally required when courts confront difficult questions). And because of the decentralized nature of the judiciary, courts cannot develop a uniform response to the pandemic, as government officials can and do. So a system in which courts can block governments but not force them to act can only weaken the public health system.

An argument could be made that if courts are willing to block governments from taking public health measures that violate civil liberties, they should also be willing to force governments to take measures to vindicate a right to health. But what we need is less judicial involvement, not more. In public health emergencies, as in war, courts do best by leaving policy to the government.

Eric Posner, a professor at the University of Chicago Law School, is the author of "The Demagogue's Playbook: The Battle for American Democracy from the Founders to Trump," which will be published in June. He wrote this article for the Washington Post.