UMass Memorial Health Care employee Therese Duke lost her job this week after a viral video appeared to show her assaulting a police officer during last Wednesday’s riot at the U.S. Capitol.

Experts say Duke's case is more clear-cut, since she was an employee at a private company and was caught on camera seemingly engaged in violence. But even public employees who are protected by their First Amendment right to peaceably assemble could be at risk of losing their jobs for so much as taking part in such violent demonstrations, according to labor attorneys who spoke to GBH News.

“Any level of involvement is going to put someone at risk at this point — particularly because of what happened last week — if there are more activities planned and someone with full knowledge has any active involvement,” Oren Sellstrom, an attorney with Lawyers for Civil Rights, told GBH News on Monday. “I think a public employer would be within rights to terminate that person for any kind of active involvement.”

Private employers like UMass Memorial have much more leeway when it comes to terminating employment, Sellstrom said, because employment-at-will states, including Massachusetts, allow employers to fire employees at any time for any reason, or for no reason at all.

“There are slightly different legal rules that apply to the two categories, but private employers can terminate employees for many different reasons, and the First Amendment doesn't apply,” Sellstrom said. “The First Amendment is about government regulation, so in general, employees are not covered in that way if it's a private employer.”

Public and federal employees are protected by the First Amendment and might have unions that could make a case for an employee taking part in such a demonstration. But if the action became violent and criminal acts were conducted, that case doesn’t hold much water, Sellstrom says.

“I think that's where it would have to be looked at on a case-by-case basis, but certainly I think the argument can be made that what started as a protest and pure speech ended up very quickly involving violent behavior,” Sellstrom said. “That link is going to be relatively easy for public employers to draw if they want to.”

A violent mob of pro-Trump extremists attacked the U.S. Capitol last Wednesday, firing weapons, destroying property and pushing past police and security. Five people died during the insurrection, and several police officers were injured.

In response, Andrew Lelling, the U.S. attorney for Massachusetts, said any state residents who took part in storming the Capitol will be prosecuted.

“The Constitution protects the right to freedom of speech and assembly. What [it] does not protect is a violent assault on government institutions. Americans on the right and left must re-learn the difference,” Lelling said in a statement Thursday. “Anyone who traveled from Massachusetts with the intent to commit such crimes will be prosecuted in the District of Massachusetts.”

Boston-based labor and employment attorney Joshua Robbins, who mainly works on private employment cases, says participation in Wednesday’s riot and any possible future actions could result in job termination — even for those who didn’t actively engage in violence.

“They're focused on the big fish right now, but it is going to trickle down,” Robbins told GBH News on Monday. “With social media, with cameras, frankly, it could be three, six months, and then all of a sudden this is at a protester's doorstop, and they thought they were in the clear.”

Monica Shah, an employment attorney with Zalkind Duncan & Bernstein LLP, says there’s a “fine line” between violence committed at the Capitol and the protesters who nonviolently participated in what became a violent action.

“Individuals have a lawful right to protest peacefully, and that should be something that is supported by employers,” Shah told GBH News on Monday. “On the other hand, if it turns into violence, if it turns into something that results in unlawful conduct, then employers may have the right to take actions based on that.”

The Massachusetts Civil Rights Act prevents private entities from interfering with an individual’s right to demonstrate, Shah says, but evaluating grounds for termination becomes murky when an employee took part in an event that became rife with criminal activity.

“I don't think it's as clear whether there's physical acts or whether someone's crossed the physical steps of the Capitol, because there is the inciting piece of things that is criminal in nature,” Shah said. “This kind of conduct could result in conspiracy charges, where somebody could think they were engaged in peaceful activity because of their involvement, but they could be swept into charges like that.”

Shah said employers, particularly public ones, should issue guidelines to their employees detailing what conduct is permissible.

“If [employees] are speaking out on a matter of public concern and protesting and not engaged in an attempt at insurrection or anything else criminal, they should be protected,” Shah said. “I think what employers and public employers may be trying to figure out is, is there a distinction between people who were there and present and those who ran into the Capitol and potentially wanted to overthrow the government? Is there a distinction between those two?”

If a public employee is terminated based on their involvement at a riot, employers “will have to go through a process of potentially establishing that the employee was not engaged in lawful First Amendment protected activity but was in fact engaged in criminal activity that warrants termination,” Shah said. “So it's a process, I think, for public employees and employers to have to go through.”

Following Wednesday’s action, some pro-Trump extremists have threatened an “armed march” on Capitol Hill and in every state capital a few days before the inauguration.

"Many of Us will return on January 19, 2021, carrying Our weapons, in support of Our nation's resolve, towhich [sic] the world will never forget!!!" one person wrote on Parler, a site friendly to right-wing extremists. "We will come in numbers that no standing army or police agency can match."

Robbins said the safest bet to avoid negative employment consequences would be to skip any upcoming protests that could devolve into a riot, but “if you're adamant about going down, I think I would spend time thinking about how this all has escalated in the past four years,” he said.

When all the risks are accounted for, including safety, employment and possible criminal issues, Robbins offered this advice: “Stay away, if possible. Find something else to do.”