The three previously imprisoned US citizens are the Iranian-American businessman Siamak Namazi, his elderly father Baquer Namazi, and Princeton University graduate student Xiyue Wang. All three are currently serving 10-year sentences on unsubstantiated and apparently unfounded charges of espionage. Wang’s arrest was motivated by his efforts to access public library documents as part of his research, yet these documents related to a period of Iranian history that ended decades before the establishment of the Islamic Republic.

It remains to be seen whether White will face similar treatment or similar sentencing, but his fellow prisoners’ cases are fairly typical of the cases involving other Western nationals who have been detained for extended periods of time in Iran, then released as part of a prisoner swaps. One of these former detainees, the Iranian-American journalist Jason Rezaian, returned to the headlines this week when it was revealed that he would be testifying in US federal court as part of a case he had filed against the Islamic Republic soon after his return to the US in January 2016.

That release coincided with the implementation of the seven-party Iran nuclear agreement, or Joint Comprehensive Plan of Action, as well as the partial repayment of an outstanding American debt to Iran, plus the release of seven Iranians and the abandonment of legal cases against 14 others who had been charged with violating US sanctions. But as detailed by Rezaian’s testimony, his release was preceded by 544 days of captivity, including 49 consecutive days of isolation in an eight foot by four foot cell, which he left only for interrogation, roughly once per day.

The Washington Post published an article on Monday describing aspects of the testimony provided by Rezaian, who had been the Post’s own Iran correspondent and now writes for its Global Opinion section. The report notes that Rezaian is requesting 44 million dollars in compensatory damages for the psychological and physical torture he experienced during his period of detention, plus one billion dollars in punitive damages as a means of encouraging Iranian authorities to reconsider their cost-benefit analysis with regard to the taking of Western hostages.

US courts have already imposed 46 billion dollars in penalties on the Islamic Republic since 1996, relying on exemptions to the Foreign Sovereign Immunities Act which allow victims of terrorism, hostage-taking, and torture to file suit against governments that, like Iran, are designated by the US State Department as terror sponsors. Collecting this money has been comparatively difficult, but another ruling against Iran may serve an arguably important symbolic role even if the money cannot immediately be collected.

Furthermore, this symbolism may be perceived as having even more value in the wake of the revelation of White’s arrest. In addition to the four US citizens and Nizar Zakka, a US permanent resident, that are now known to be held in Iranian prisons, another such citizen, former FBI agent Robert Levinson has been missing since 2007, when he disappeared from Iran’s Kish Island while working a case as a private investigator. Levinson’s family continues to maintain that he is alive and that the Iranian regime knows his whereabouts. If this is true, it would make Levinson the longest-held hostage in American history.

But prospects for recovering Levinson alive are made dimmer by his advanced age and the notoriously harsh conditions of the Iranian criminal justice system. On Thursday, CBS News described some such conditions in order to highlight the hardships that Michael White has likely faced during his more than six months of secretive detention. The outlet’s reporting drew upon testimony from Ivar Farhadi, a former Iranian political prisoner who claims to have met White in prison, as well as from CBS reporter Roxana Saberi, who was held falsely accused of espionage and detained in Iran for 100 days in 2009, at the time of the Green Movement uprising.

“There is a pattern,” Saberi said of her knowledge of politically motivated arrests in the Islamic Republic. “Typically, you’re first put in solitary confinement where you’re cut off from the outside world. You don’t get any phone calls. You don’t have access to an attorney… You also undergo intense interrogations.”

Farhadi could not definitively state whether White was being tortured during the time they were fellow inmates, since their interactions were monitored and discussion of such sensitive topics would have prompted extrajudicial punishment or the filing of new national security charges. But Farhadi was able to confirm that White was “suffering psychologically” and that he was being housed alongside violent offenders, in defiance of Iranian laws calling for the separation of inmates based on the category and seriousness of their crime. The intermingling of political prisoners and dangerous criminals is a common pressure tactic in Iranian prisons, as is physical abuse, poor sanitation, and the withholding of medical treatment.

According to another CBS News report, this latter tactic may present a particularly serious risk to White, as he had recovered from cancer shortly before his trip to Iran. The lack of medical care is a topic of protest for many detainees, but prison authorities often respond with further crackdowns. It was recently announced that the renowned human rights lawyer Narges Mohammadi and Nazanin Zaghari-Ratcliffe, another imprisoned dual national, would be jointly undertaking a three-day hunger strike because of their concerns over deteriorating and untreated health conditions as they serve sentences on false national security charges.

Like White, Zaghari-Ratcliffe is also contending with the danger of cancer, having found lumps in her breast sometime last year. She is also reported to be suffering from an unspecified neurological condition, with symptoms including loss of equilibrium and severe numbness in her extremities. But in spite of all this, officials not only continue to deny the prison doctor’s requests for her transfer to hospital, but are also punishing her for speaking out.

It was previously reported that Zaghari-Ratcliffe’s telephone calls with her husband in the United Kingdom were cancelled immediately after announcement of the forthcoming hunger strike. And on Thursday, Agence France Presse reported that Iranian state media had aired footage of her April 2016 arrest as part of a multi-part propaganda series aimed at convincing citizens that there is a crisis of “interference in domestic affairs” by “enemies” of the Islamic Republic. The program did not, however, present any new information to support the claim that Zaghari-Ratcliffe was part of an “infiltration network” working toward the “soft overthrow” of the theocratic regime. Her arrest appears to have been motivated by her identity as a dual national and her employment history, which includes a period spent working for the charitable arm of the British Broadcasting Corporation.

Standing alongside the acknowledgement of White’s arrest, the new propaganda broadcasts regarding Zaghari-Ratcliffe and other dual nationals are easy to regard as evidence that the problem of Iran’s crackdown on such individuals is only getting worse. Soon after taking office in 2017, US President Donald Trump promised to prioritize the release of those who remained hostages in the Islamic Republic. But the families of those hostages have been variously critical of the White House’s action, or arguable lack thereof, over the past two years. The surprise revelation of White’s ongoing detention may only serve to amplify these criticism, in light of the fact that the State Department failed to inform the prisoner’s family of his situation until three weeks before the report emerged.