WASHINGTON — Many of the nation's mayors and governors are ordering schools, courthouses and even large public gatherings shut down, but where do they get the power to do that?
Every state in the United States — and virtually every country in the world — has laws conferring this legal authority. They're some of the oldest on the books, stemming from the plagues of past centuries that devastated Europe and were reworked again after the 1918 Spanish flu epidemic and the more recent Ebola outbreak.
"There's no question that states have very broad powers to do rather extraordinary things in public health emergencies," professor Wendy Parmet, an expert on public health law at Northeastern University, says.
President Donald Trump will declare a national emergency Friday, but that largely would provide more assistance to state and local governments and would not enlarge federal power to restrict public gatherings or travel. It provides the same kind of aid that is made available in response to national disasters like hurricanes.
The federal government has long had authority to prevent people who could be carrying disease from entering the country. Trump imposed the European travel ban under his general power to restrict immigration.
Federal law says the president can suspend the entry of any noncitizens "whenever the president finds that the entry of any aliens or of any class of aliens into the United States would be detrimental to the interests of the United States." It's the same provision Trump invoked in the past, with varying degrees of success, to limit travel from mostly Muslim countries and to restrict immigration at the southern border.
Chief Justice John Roberts referred to this power two years ago when the court upheld a modified version of Trump's Middle Eastern travel ban. If the opponents were right about the limits of the law, "the president would not be able to suspend entry from a particular country in the event of an epidemic in that country or even if the United States were on the brink of war with that country."
Separately, federal public health laws give the Centers for Disease Control and Prevention the authority to detain and examine anyone arriving in the U.S. suspected of carrying a communicable disease. The federal government could even limit travel from one state to another by people deemed a public health risk, though the practical limitations of actually doing it make that largely theoretical.
Professor George Annas, a public health law expert at Boston University, said, "I don't think you're going to see any restriction on interstate travel in the United States."
Most of the restrictions popping up now in response to the coronavirus pandemic are local ones. All states and the District of Columbia have laws, as part of their general police powers, authorizing quarantine, which is a restriction on people who may have been exposed to see if they become sick, and isolation, which is intended to stop people known to be sick from spreading a disease.
While these laws vary widely, most give governors or public health officials authority to limit public interactions in emergencies.
Washington state's law, for example, says the governor "after proclaiming a state of emergency ... may issue an order prohibiting ... any number of persons, as designated by the governor, from assembling or gathering on the public streets, parks, or other open areas of this state, either public or private."
That includes banning such nongovernment gatherings such as sporting events or concerts. The ability of private businesses to successfully challenge these restrictions is very limited, assuming the state and local authorities follow the rules and don't act irrationally or with intent to illegally discriminate.
"If somebody were to challenge something like (New York) Gov. Andrew Cuomo's containment order or the one shutting down Broadway, I think it would be very hard in this climate to prevail in court," Parmet said. "Things may change depending on how long this goes on, but courts have traditionally been extremely deferential to public health emergency powers."
Some states restrict how local officials can close public gathering places, and places like movie theaters can be closed without further authority from a legislature, Annas says. "In general, as long as you have the support of the public, the power is nearly unlimited."
President Bill Clinton used that authority in 2000 to help New York and New Jersey deal with an outbreak of the West Nile virus, allowing them to conduct spraying against mosquitoes that spread the disease. President Barack Obama, under the same law, made federal support available to West Virginia and Flint, Michigan, when water supplies were contaminated.