Judge Napolitano

On a brand new Judging Freedom, Judge Andrew Napolitano discusses the news that New York City has set a COVID-19 vaccine mandate for private-sector works.

This new ‘first in the nation’ requirement is scheduled to go into effect on December 27th, says outgoing New York City Mayor Bill de Blasio.

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The new mandate comes after New York identified eight cases of the omicron variant and the United States once again averages 100,000 new, reported cases of the virus every day. It will cover about 184,000 businesses and applies to all in-person employees who work in an office with others.

By Dec. 27, unvaccinated employees must have received at least one dose of the coronavirus vaccine, de Blasio said. Under the new mandate, unvaccinated employees won't have the option to get tested instead, but the city plans to offer religious and medical exemptions.

"We've got omicron as a new factor, we've got the colder weather, which is really going to create additional challenges with the delta variant, we've got holiday gatherings," de Blasio said during his appearance on MSNBC's "Morning Joe." "We in New York City have decided to use a preemptive strike to really do something bold to stop the further growth of Covid and the dangers it's causing to all of us."

Nearly 78% of New York City residents have received at least one dose of the coronavirus vaccine as of Dec. 6.

Below, two public health experts and an employment lawyer explain how the new vaccine mandate could help curb the spread of the virus and what challenges the new rules could bring.

Dr. Robyn Gershon, a clinical professor of epidemiology at the NYU School of Global Public Health, tells CNBC Make It that she wouldn't be surprised to see other cities announce similar vaccine mandates, calling it "an essential move" for the United States to reduce the threat of the virus.

Other large, densely populated cities would especially benefit from a vaccine mandate for private companies, she adds, because it's easier for the virus to spread in such environments. "They'd be crazy not to mandate vaccines, because it's in their best interest," Gershon says. "People have a pent-up desire to dine out, go to restaurants and 'return to normal,' but we need to be safe … the best way to do that is to get vaccinated."

Other cities with large business communities like Boston or Los Angeles could emulate the mandate, says Dr. Gigi Gronvall, a senior scholar at the Johns Hopkins Center for Health Security at the Bloomberg School of Public Health. But they might be less effective implementing such rules.

"New York City holds more business and political cards than most cities," Gronvall notes. "For example: people who work in New York City, but don't live there, still have to pay New York taxes — a lot of cities wouldn't get away with that."

Another factor that will determine when and how other cities will follow suit is how prepared cities are to implement such a mandate. That includes having sufficient vaccine supplies, available appointments at pharmacies, a system to track vaccinations and enough health-care professionals to administer the shots.