Good luck with that.
That, in a nutshell, was the take Wednesday from public health and policing experts after the governors of New York, New Jersey and Connecticut announced that travelers from states where the coronavirus is raging would be required to self-quarantine for two weeks.
They said that the order is unenforceable and that it borders on the unconstitutional, and one pundit suggested that it smacked of political payback against Florida Gov. Ron DeSantis, who had required New Yorkers to self-quarantine for two weeks back in March when coronavirus cases were spiking in the state.
"I don't know how you enforce something like this," said Brian Higgins, an expert on crowd management security at the John Jay College of Criminal Justice in New York City. "People are always going back and forth between states like New York and Florida, and if they're not flying, they're driving.
"I suppose if they really wanted to, they could start tracking people through E-ZPass, but I just can't imagine they would go that far," added Higgins, who previously was chief of police in Bergen County, New Jersey.
Dr. Sadiya Khan, an epidemiologist at the Northwestern University Feinberg School of Medicine, agreed.
"The U.S. is not China. We're not going to order a military lockdown," Khan said. "It is sound advice to ask people from states with high levels of infection to self-isolate for two weeks. But I'm skeptical of how these restrictions can be forced."
New York Gov. Andrew Cuomo, New Jersey Gov. Phil Murphy and Connecticut Gov. Ned Lamont said the quarantine order applies to states where coronavirus infection rates are spiking, including Alabama, Arkansas, Arizona, Florida, North Carolina, South Carolina, Washington, Texas and Utah.
"It's only for the simple reason that we worked very hard to lower the infection rate, and we want to keep it down," Cuomo said, adding that those states have been targeted because all have positive coronavirus test rates of 10 percent. "People could bring the infection with them."
Cuomo also insisted that there would be a price to pay for violating the rule, specifically fines of $2,000 to $10,000.
"No. You violate the quarantine, you will then have to do a mandatory quarantine, and you'll be fined," he said.
Hotel clerks would notify authorities about violators, and police would pull over motorists with license plates from states on the quarantine list, Cuomo said.
Lamont was somewhat vaguer about how the order would be enforced.
"What we are going to do is every single airport throughout our region, people will be noticed that these are the rules, you must self-quarantine if you haven't had a test within 72 hours, something like that," Lamont said later on a call into the Fox Business Network. "We are going to notify hotels and Airbnbs that these are the rules so that people will know what the rules of the road are and they'll follow them."
Polly Price, a professor of law and public health at Emory University in Atlanta, said the problem with such pronouncements is that they bump up against U.S. citizens' constitutional right to travel from one state to another.
"No state can prevent you from coming in," Price said. "What these states are doing is imposing conditions on that travel. When it goes from 'we're going to request that you self-quarantine for a period of time' to 'we're going to arrest you or fine you if you don't,' that's when constitutional issues become tricky."
The U.S. has enacted international travel bans. For example, on Jan. 31, President Donald Trump barred foreign nationals who had traveled to China within the previous 14 days from entering the U.S., but not U.S. residents or their relatives. The move came 10 days after the first confirmed case of the coronavirus was reported near Seattle.
"The problem is, within the U.S., states can't do that, because we have a fundamental right to travel from state to state," Price said.
Last month, a federal judge struck down Kentucky's attempt to ban people from entering from other states with worse outbreaks, and he suggested in the footnotes that Kentucky follow the model of neighboring Ohio, where rules are "requests for the most part."
"Ohio's rules, there, do not appear overboard and have a rational basis for combating the coronavirus, while still preserving the population's constitutional rights," U.S. District Judge William Bertelsman wrote.
In Hawaii, which has had very few coronavirus cases, the Justice Department on Tuesday called the state's 14-day quarantine rule for out-of-state and international travelers discriminatory and filed a legal challenge arguing that it "likely violates" constitutional protections of interstate travel.
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DeSantis' executive order required that people entering Florida from New York self-quarantine for 14 days. Rhode Island Gov. Gina Raimondo went a step further and dispatched State Police to stop motorists with New York license plates to inform them of her 14-day self-quarantine order.
DeSantis, who has taken a lot of heat for Florida's slow response to the crisis, later claimed that his move saved a lot of lives.
"I quarantined them in March, and everyone in the New York media was blowing a gasket — 'How could you do this?'" DeSantis said later.
Right now, however, Florida is experiencing a record spike in new infections, as are states like Texas and Arizona. There is no evidence yet that the Black Lives Matter protests that have swept the nation for the last three weeks are fueling the sudden rise.
DeSantis did not immediately respond to a request for comment now that New York is asking Floridians to quarantine. But earlier Wednesday, Frank Cerabino, a longtime columnist for The Palm Beach Post, wrote that Cuomo was giving DeSantis "a little bit of his own medicine in interstate coronavirus posturing."
"Instead of taunting New York, Florida's leaders would have been better off emulating New York's response to the community spread of the virus," Cerabino wrote.