(NEW YORK) — Tens of millions of Americans have been vaccinated against COVID-19 and with that, workplaces around the country are opening up once again.

But the rules that some employers and others have put into place mandating vaccines that are still not fully authorized by the Food and Drug Administration, have sparked showdowns with employees.

Lawsuits have been filed against a Texas hospital, a Los Angeles school district, a North Carolina sheriff and a New Mexico detention center, to name a few.

And with a portion of the population hesitant to get vaccinated, including some who outright refuse, there may be more showdowns down the line. A May report by the Kaiser Family Foundation, a non-profit that conducts research on key health policy issues, found nearly a third — 32% — of unvaccinated adults are waiting for full FDA approval of a vaccine before getting it.

The central argument in the suits is the vaccines are allegedly “experimental” because they only have emergency authorization — and therefore, they cannot be mandated.

Allison Hoffman, a professor of law at University of Pennsylvania who specializes in health law, told ABC News these complaints “are not very strong legal arguments,” noting that employers can legally require workers to get the shots because the FDA’s emergency use authorization (EUA) means the shot is safe enough for the public.

The Centers for Disease Control and Prevention (CDC) has also said vaccines approved under EUA are “safe” and “effective.”

‘Not coercion’

In Texas, a judge recently sided with Houston Methodist Hospital’s vaccine mandate for their employees and tossed out a lawsuit filed by 117 employees who were against getting the shot.

U.S. District Judge Lynn Hughes dismissed the action on June 12, saying, “This is not coercion … The public’s interest in having a hospital capable of caring for patients during a pandemic far outweighs protecting the vaccination preferences.”

The hospital, which has over 26,000 staffers, set a June 7 deadline for staffers to get the shot. In the end, 178 employees who did not comply with the mandate and were not granted an exemption or deferral, were suspended for 14 days without pay. If they do not get vaccinated within two weeks, they will be terminated, a spokesperson for the hospital told ABC News.

The lawsuit argued that the COVID-19 vaccine only received emergency authorization from the FDA but was awaiting full approval, and alleged the hospital was violating the Nuremberg Code on Permissible Medical Experiments, which ban forced medical experiments and mandates voluntary consent.

Jared Woodfill, the attorney representing the plaintiffs, previously told ABC News he plans on appealing the decision. He said the case is “just one battle in a larger war to protect the rights of employees to be free from being forced to participate in a vaccine trial as a condition for employment.”

Hoffman said the argument that the vaccine isn’t safe under EUA and is akin to human experimentation is “a stretch.”

“The vaccines were tested rigorously before they were given emergency use authorization. And even to get emergency use authorization, they’ve gone through the kind of safety testing that anything would go through before getting the full authorization as well. So they’re not experimentation at this point,” she said.

Fired by sheriff’s department

Another such lawsuit was launched in North Carolina by former Durham County deputy Christopher Neve. The federal suit, filed against Sheriff Clarence Birkhead on April 14, claimed Neve was fired because he didn’t comply with the sheriff’s vaccine mandate for department staffers.

Neve, who worked for the sheriff’s office for five years as a school resource officer and patrol officer, was put on leave on March 12 and fired two weeks later — about two months after Birkhead issued a memo about the vaccine mandate and offered staffers the option show a doctor’s note for an exemption, according to the complaint.

The lawsuit sought to invalidate the mandate and asked for Neve to be reinstated with back pay and benefits. The lawsuit also argued that mandating a vaccine that only has emergency authorization violates federal law.

“These vaccines are not free from risk. In the clinical trials, which are still underway, there were serious adverse events documented following vaccination found by the trial investigators to not only be ‘linked’ to the vaccines, but in fact related to the vaccines,” the lawsuit states.

The CDC notes that the approved COVID-19 vaccines may have some side effects such as pain, headache, muscle pain and fever, which are considered normal and go away on their own.

The lawsuit also cites that under the FDA’s EUA, recipients must be informed by the FDA of “the option to accept or refuse” its administration.

The EUA guidance also states recipients must be informed of “the consequences, if any, of refusing administration of the product” by the FDA. Hoffman said “consequences of refusal might include that you can’t have access to certain things like a job where you’re being unvaccinated is unsafe to others.”

The Durham County Sheriff’s Office said it does not comment on pending litigation and said the lawsuit is still pending in federal court. All of the department’s 429 employees have been vaccinated with the exception of 20 who are exempt for either medical or religious reasons, a department spokesperson told ABC News.

Birkhead’s lawyers declined to comment and Neve’s lawyer did not respond to ABC News request for comment.

‘We draw the line’

In Los Angeles, the Los Angeles Unified School District was sued in March by a group called California Educators for Medical Freedom, a grassroots coalition of LAUSD employees who came together after news surfaced that the district allegedly intended to create a vaccine mandate. The lawsuit claimed that the district issued guidance to employees that was interpreted as a vaccine mandate that threatened discipline if staffers did not comply.

Schools across the country have asked employees to get the vaccine, in part, due to the fact that children under the age of 12 are not eligible for the shot yet.

According to the suit, an e-mail from a representative of LAUSD’s operations department said: “All District employees will be required to be vaccinated. No exceptions have been made…”

“We are ready to provide top notch in person services and instruction with safety measures in place like medical screening, hand washing stations, hvac ventilation, and physical distancing.  But we draw the line at being forced to take an experimental vaccine with unknown long term side effects,” the group California Educators for Medical Freedom’s website states.

However, a LAUSD spokesperson told ABC News it never enacted a vaccine mandate.

“Los Angeles Unified has not mandated COVID-19 vaccinations for employees. Instead, we are providing access to the vaccine for all who work in schools and encouraging them to get vaccinated. The choice is theirs,” the statement said.

John W. Howard, the lawyer representing California Educators for Medical Freedom, told ABC News that he has “offered to settle the case if [LA United] will do one thing: state on the court record that vaccination is not mandatory; that it is entirely voluntary and that LAUSD will not require it unless the vaccines are approved by the FDA and removed from EUA status. They have refused.”

And in New Mexico, Doña Ana County Detention Center officer Isaac Legaretta, who faced termination for not getting the vaccine, filed a lawsuit in February against county manager Fernando Macias and jail officials over the vaccine requirement.

Macias issued a directive on Jan. 29 requiring county-employed workers, such as first responders and detention center officers, to receive the vaccine, according to the lawsuit. Lagaretta never submitted a proof of vaccination or a documented reason for an exemption and on Feb. 17 he was issued a notice to get vaccinated within five business days.

In the suit he said he was in “imminent danger of being terminated.” He asked for a court order to prevent his employer from coercing him and others from getting the shot. Legaretta’s suit argued, just as the others, that shot had not been fully approved by the FDA.

Legaretta was demoted after he refused the vaccine and ended up quitting shortly after the lawsuit was filed, his lawyer, Jonathan Diener, told ABC News. They have amended the complaint to argue that the county “violated his constitutional rights by forcing him to get a vaccine or else lose his job,” Diener said.

So can vaccines be mandated?

The central question raised by the suits is whether employers have the power to mandate vaccines from employees.

Under Equal Employment Opportunity Commission (EEOC) guidelines, the answer is yes, if the right accommodations are made.

Employers have the power to set vaccine mandates for various diseases — including flu, measles, mumps, and in May the EEOC said employers can also require staffers to be inoculated against COVID-19. However, workplaces must make accommodations to workers who decline the vaccine due to health conditions or a religious belief.

Accommodations might include allowing an unvaccinated employee to wear a face mask and social distance while at work, working a modified shift, getting periodically tested for COVID-19 or being given the opportunity to telework or accept a reassignment, according to the guidance.

Hoffman said Houston Methodist and Durham County were within their rights to terminate staffers because they offered those key considerations.

“Now, if we saw an employer not operating within those bounds, so not making the kind of exemptions or making reasonable accommodations, then I think you see, you would see stronger legal grounds on which to stand. But that’s not the case with Houston Methodist,” she said.

Hoffman said these legal challenges “could very well make it up to the Supreme Court,” because there is little legal precedent. However, these challenges “are going to become stale very quickly, because we’re not going to be under emergency use authorization much longer.”

Pfizer applied for full licensing in May and Moderna applied in early June. Johnson & Johnson has not asked for their vaccine to be fully approved yet.

Drugmakers have to submit six months of data for full Biologics License Application (BLA) approval and the FDA will take several months to review the full set of data before granting it.

“Probably by sometime this fall or the winter there will be full licensing approval, so even as these cases work their way through the courts, I would imagine that Pfizer, and then shortly after the Moderna vaccines will have that full approval,” Hoffman said. “So then the issue will no longer be what lawyers call, ripe for the court to look at.”

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