Just a few months into the coronavirus pandemic, Holly Smith had already made up her mind. She was not going to reopen her restaurant to diners until there was a vaccine. She just didn't think it was safe. When she shared the decision with her staff, they asked: Would the vaccine be mandatory?

Yes, she said. It would be.

"I'm not going to open until I can indeed be sure that everyone on my staff is vaccinated," says Smith, chef and owner of Cafe Juanita in Kirkland, Wash. "The immediate people on the team — you've got to take care of them. If you don't take care of them, they cannot help you take care of business."

With promising news from three COVID-19 vaccine trials showing 90% to 95% efficacy, employers are now weighing whether they should simply encourage their employees to get vaccinated or make it mandatory.

The U.S. Occupational Safety and Health Administration has stated that employers can legally impose a flu vaccine requirement on their workforce, but employees have the right to request medical or religious exemptions under federal anti-discrimination laws. Each claim must be evaluated on its own merits, a time-consuming process for employers.

While it may be legal for employers to compel their workers to get the COVID-19 vaccine, doing so would be a huge, difficult undertaking, says Y. Tony Yang, executive director of the Center for Health Policy and Media Engagement at George Washington University, who has argued against COVID-19 vaccine mandates.

"It's going to have lots of pushback, and lots of people are going to claim exemptions" out of concern about the safety of the vaccine, he says.

A recent Gallup poll found that 42% of Americans say they will not get the COVID-19 vaccine, though the poll was conducted before the recent optimistic vaccine results.

The pork producer Smithfield Foods, which sustained a coronavirus outbreak early in the pandemic that infected nearly 1,300 workers according to OSHA, says it does not anticipate a firm mandate at this time, even as the company has requested priority access to the vaccine for food and agricultural workers. Smithfield is aiming to offer the vaccine on site once it becomes available.

Frozen food manufacturer Bellisio Foods is also planning for on-site COVID-19 vaccinations but does not expect to require employees to take part.

"I don't think that we would mandate it but, you know, I didn't think we'd be taking temperatures either," says Margot McManus, Bellisio's chief people officer. "We can always change our mind."

Despite the minefield, Johnny Taylor Jr., president of the Society for Human Resource Management, predicts many employers will opt for mandates, more now than he would have guessed several months ago. Employers have an obligation to get rid of known hazards in the workplace, he says, and COVID-19 has proven to be a hazard unlike any other.

"It's real, and it's devastating," he says. "So, I think the dynamic changes. Employers are actually going to position this as, I need to do this, full stop."

That has been Smith's position even as she's struggled to keep her restaurant alive. Before the pandemic, Cafe Juanita had 28 employees. She's had to lay off all but five as her fine dining spot has become a takeout-only business.

Even with a much smaller staff, Smith follows strict safety protocols, including requiring that her workers get tested if they go on vacation with people outside their bubble or if they're showing any sign of illness.

"I believe in civil liberties," she says. "But we have people who live with their parents. We have people who live with a husband who has diabetes. There are people who have immunocompromised folks in their immediate bubble."

This fall, Smith made sure all of her staff got the flu shot, putting her in line with many health care employers who have long required it for their workers.

At Baylor College of Medicine in Houston, some 14,000 employees and students are required to get the annual flu vaccine, says Dr. James McDeavitt, dean of clinical affairs. About 90% actually do, with 10% claiming exemptions, most of them medical, according to his analysis.

"It's the right thing to do for society," he says, noting that the mandate covers not just doctors, nurses and medical students, but also people working in billing and other jobs that don't put them in contact with patients. Those who go unvaccinated are required to wear masks in the workplace.

McDeavitt says Baylor will impose a COVID-19 vaccine mandate but not before they can actually get enough supply to cover everyone and it's been deemed safe by the Food and Drug Administration and Baylor's own epidemiologists, vaccine scientists and infectious disease doctors.

"[They] will look hard at the data and tell me, yes, this was done properly," he says. "So when I start giving the vaccine to my employees, you can be assured it is safe to give it to your employees."

Still, there will be legal challenges, says Taylor, whose organization represents 300,000 HR and business executives. He is now calling on Congress and state legislatures to enact greater protections for employers.

"The employer is truly in a no-win situation from a risk standpoint," he says. Those who decide to mandate the vaccine will need protection against someone having an adverse reaction, even if the employee has signed a waiver upon receiving the shot, he says. Conversely, companies that decide against a mandate will need protection if someone does contract the virus in the workplace and sues.

Taylor has been meeting with federal officials from the Equal Employment Opportunity Commission, telling them employers want to do the right thing.

But they are in a tough spot, he says, and they're going to need help getting through this.

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