The decades-long prison sentences for a group of Texas activists convicted of terrorism and other charges in connection to a Fourth of July protest last year has caused widespread alarm, given their unusually punitive length and for the apparent harsh criminalization of protest activity under Donald Trump’s justice department.

Eight people who participated in a protest at the Prairieland ICE detention facility in Alvarado, Texas, were sentenced on Tuesday to between 50 and 100 years in prison. A ninth person, Daniel Sanchez-Estrada, the husband of one of the demonstrators, did not participate in the protest, but was sentenced to 30 years in prison after he was convicted of moving boxes containing leftwing zines and other materials after a prison phone call from his wife.

“These sentences are a travesty and totally unjustified, but that’s the point. Americans hate the fascist Trump regime, so the only way they can try to cling to power is brute force,” the representative Rashida Tlaib, a Democrat from Michigan, posted on X. “More bullshit ‘terrorism’ charges like these are coming.”

Sanchez-Estrada’s sentence in particular has been condemned by first amendment advocates, who say that it sends a chilling message about the kind of ideological material people are allowed to possess.

The zines Sanchez-Estrada was punished for moving are “no different from the pro-Revolution pamphlets this country’s founders had in mind when they drafted the first amendment’s press clause,” said Seth Stern, the chief of advocacy at the Freedom of the Press Foundation.

“Sanchez’s case is the latest example of the Trump administration grasping at any legal straws it can to criminalize disfavored ideologies and writings, from conflating dissent with terrorism to deporting immigrants who report on protests or criticize wars the US bankrolls,” he said in a statement.

“Americans should not make the mistake of believing Sanchez’s sentence only threatens immigrants, leftists or so-called antifa members – they’re just the low-hanging fruit, not the endgame.”

The prosecution was closely watched because it was the first case to go to trial after the Trump administration vowed to crack down on “antifa” – which is not an organization but a constellation of leftwing ideologies. Prosecutors claimed the demonstrators were part of “antifa” and filed a broad terrorism charge against them, allowing the Trump administration to claim they had successfully convicted antifa terrorists. The actual terrorism charge the government got a conviction on, however, is not connected to ideology.

Of the other seven defendants, five of them received 50-year prison sentences. That includes two people who were not involved in planning the protest, arrived late and left when guards asked them to. Sanchez-Estrada’s wife, Maricela Rueda, was sentenced to 70 years in prison. Benjamin Song, the lone person who fired at a police officer and hit him, was sentenced to 100 years in prison. All are likely to pursue an appeal of both their sentence and conviction.

“The government wants to take her entire life away because she attended a protest. Nobody died,” Lydia Koza, whose wife, Autumn Hill, was sentenced to 50 years in prison, told the Associated Press.

Those punishments are unusually long, sentencing experts said. Both of the judges overseeing sentencing – Donald Trump appointee Mark Pittman and George W Bush appointee Reed O’Connor – stacked the sentences for the multiple convictions.

“It’s relatively unusual to see that kind of stacking,” said Mark Osler, a law professor and sentencing expert at the University of St Thomas in Minneapolis. “Usually the sentence for the core offense is pretty harsh in the federal system, frankly, and there’s no need to pile things on.”

O’Connor explained his harsh sentences as necessary to send a message. “The need to deter this type of conduct is high,” said O’Connor, who also called the attack an “assault on democracy”, according to the Associated Press.

While the government’s sentencing recommendations remain sealed in the case, the recommended sentences could have been inflated by a terrorism enhancement under the federal sentencing guidelines because of the specific crimes they were found guilty of. The enhancement drives up the seriousness of the offense and the relevant criminal history in the calculation judges rely on for a recommended sentence, said Osler and Douglas Berman, a law professor at the Ohio State University who is also a sentencing expert.

“It does this sort of double whammy that functionally makes the sentence recommendation from the guidelines extremely long,” Berman said. “I still can say these are extreme sentences.”

Even with a recommendation from the federal sentencing guidelines, judges still have discretion to depart from them. “Judges very often go below the guidelines, much more often than they go above,” Osler said.

A federal judge in Maryland, for example, recently sentenced a woman who pleaded guilty to attempting to assassinate the supreme court justice Brett Kavanaugh to eight years in prison, even though federal sentencing guidelines recommended 30 years to life, according to the Washington Post. The justice department is appealing the sentence to the US court of appeals for the fourth circuit, saying it should be longer.

Still, experts said they were most puzzled by the long sentence for Sanchez-Estrada.

“The 30-year sentence for Estrada is probably the one that for most people will come closest to shocking the conscience,” Osler said. “Simply because this is an activity that took place after the harm occurred. And it’s something that’s done, you know, within a family context, and frankly, which many people can imagine themselves doing in a similar situation – even if they can’t imagine themselves firing a gun at a federal facility.”

Frank Gatto, a federal prosecutor, said during sentencing: “People with that kind of extremist beliefs need extra time in prison. They believe violence is justified.”

Phillip Hayes, an attorney for Song, said the activists were “a bunch of kids and young adults who really have a really big heart and really wanted their voice to be heard. It was never intended that anybody get hurt. It was never intended that any shots would be fired.”