. Iran and the US have not had formal diplomatic relations since the 1979-80 hostage crisis at the US embassy in Tehran. Switzerland handles American consular affairs in the Islamic Republic, in situations where it is permitted to do so.

The prisoner, Michael White, is serving a 10 year sentence on the basis of vague charges including “insulting the supreme leader.” He was initially taken captive in July 2018, but his case was not made known to Western media until several months thereafter. When Iranian officials finally acknowledged his arrest, they predictably rejected the notion that it warranted diplomatic involvement, and the judiciary alleged that his case stemmed from a “private complaint.”

This has never been explained, though it may have something to do with the nature of White’s trip – a visit with his Iranian girlfriend. The Islamic Republic enforces strict laws concerning gender segregation and female modesty. As evidenced by worsening crackdowns on protests against the country’s forced veiling laws, the consequences of these laws are usually borne by Iranian women, who are afforded lesser standing under Iranian law.

Foreign and dual nationals have also seemingly been subject to worsening crackdowns in recent years. At least three other American citizens are currently being held in Iranian prisons, and each is serving the same 10-year sentence as Michael White. However, the charges filed against him differ from those of the other three men. The others have all been accused of some form of espionage, although little to no evidence has ever been cited to substantiate these charges.

In the case of Wang, the accusation appeared to contradict the explicit permission that he had been given to conduct research in the Islamic Republic. As part of that research, he accessed materials in Iranian public libraries having to do with the Qajar dynasty, which ended decades before the Islamic revolution. There is no indication that he ever attempted to access sensitive materials, much less that he did so successfully, and yet his research laid the foundation for accusations of spying on behalf of the United States.

The charges against White are even vaguer. And even if the Iranian judiciary had established how he had insulted the supreme leader, such a charge would of course not be recognized as a crime by the international community. For these and other reasons, his arrest and sentencing have been widely interpreted as the latest example of hostage-taking by hardline Iranian authorities, who may intend to use these Western nationals as bargaining chips in negotiations with their countries of origin.

This intention has been all but confirmed in the case of a high-profile hostage from the United Kingdom. Nazanin Zaghari-Ratcliffe has been held at Evin Prison since April 2016, after she was detained at Imam Khomeini airport and accused of playing a leading role in a Western-organized “infiltration network.” The accusation likely stemmed from her British citizenship and also her past affiliation with the British Broadcasting Corporation. However, that affiliation involved only the charitable wing of the organization, which is separate from its news divisions, and she has never been professionally involved in journalism or politics.

The particular tensions between Iran and the UK became especially pronounced in mid-July when the Islamic Revolutionary Guard Corps seized a British-flagged vessel less than two weeks after British Royal Marines detained a supertanker that was passing by Gibraltar with an estimated two million barrels of oil headed for Syria. Tehran officially denied any connection between the two incidents, but IRGC officers had already promoted the idea of a retaliatory seizure after UK moved to enforce European Union sanctions on transactions with Syria.

The Iranian tanker, formerly known as the Grace 1 and lately renamed the Adrian Darya 1, was released from Gibraltar in late August, but the Stena Impero remains in Iran. Iranian authorities are likely waiting for their own ship to offload its oil and arrive safely at port before engaging in further tit-for-tat, and it remains unclear whether the Adrian Darya will actually find any place to make landfall. This is because the US strenuously objected to the release in the first place, and has since warned all allies and economic partners against any move to assist the vessel.

The White House believes the Adrian Darya to be wholly owned by the IRGC, meaning that the sale of its oil could be used to finance further malign activities by the Revolutionary Guards and their affiliates. These malign activities might include the further taking of hostages who hold citizenship in the US, Britain, or elsewhere in the West. The two leading Western powers are by no means the only nations to be targeted with this strategy. Meanwhile, Iran’s decision to continue holding British property in response to American actions underscores the regime’s failure to adopt separate foreign policies for the US and its allies.

In August, it was reported that another Iranian-European dual national, Ahmadreza Jalali, was under pressure to issue false confessions that might substantiate the death sentence already handed down on him. Jalali, a medical doctor and researcher in crisis management, was living in Sweden until the time when he was arrested after returning to the Islamic Republic for an academic workshop, upon the invitation of two Iranian universities. He was charged with espionage and “enmity against God” for supposedly “transferring sensitive projects documents related to research, military, defense, and nuclear” matters. The alleged recipients were in Israel, though Tehran’s public prosecutor suggested that the Swedish citizenship was a form of payment for Jalali, his wife, and their two children.

Jalali was taken to an unknown location on July 29 and only returned to his cell at Evin Prison on August 7. Afterwards, he informed his wife by phone that the authorities had threatened him with accelerated implementation of his death penalty unless he signed a confession. Such efforts to fabricate evidence are no doubt indicative of the authorities’ own awareness of the weakness of the case, despite their ability to secure a prior conviction. Iran’s Revolutionary Court, which handles alleged national security crimes, is widely recognized for a tendency to follow the IRGC’s lead and make determinations of guilt before evidence has even been presented.

Persons convicted in that court are frequently subject to extrajudicial pressure, even in cases where the authorities do not appear to be pursuing false confessions in order to counter skepticism about the conviction. Jalali is arguably representative of both phenomena. At the same time that he has faced threats of violence, he has also been routinely deprived of medical treatment, which is a common tactic of extrajudicial pressure in Iranian prisons.

In this way, Jalali’s case is similar to that of both White and Zaghari-Ratcliffe, and his family’s concerns are reminiscent of those expressed in recent days by White’s mother and Zaghari-Ratcliffe’s husband. Jalali was briefly transferred to hospital in November of last year, where he underwent surgery in connection with severe stomach pains before being quickly returned to his cell. Since then, he has received sparse medical attention, if any, despite the fact that he is believed to be suffering from cancer.

White and Zaghari-Ratcliffe have each experienced cancer scares during their time in prison, as well. In either case, the harsh conditions of Evin Prison have seemingly exacerbated health problems – both physical and psychological. And those conditions have only grown worse in recent weeks, with prison officials arbitrarily blocking phone calls with her husband and visits from her five-year-old daughter Gabriella, who was prevented from leaving Iran after her Zaghari-Ratcliffe’s arrest and is now being cared for by her Iranian grandparents.

Of his wife’s psychological health, Richard Ratcliffe said, “She is in varying levels of despair,” and this has been made worse by concerns that her case will receive less attention as other aspects of the Iranian crisis grow. Mr. Ratcliffe echoed those concerns while highlighting his past disappointment with the British government’s approach to resolving his wife’s case. Similar disappointment has been expressed on the other side of the Atlantic by advocates for Americans who remain detained or missing in Iran despite President Donald Trump’s repeated promises to make their release a priority.

Reiterating a sentiment that has been expressed by various Iranian political prisoners’ loved ones, Michael White’s mother Joanne told CBS News, “I’m really worried that… If they don’t release him on appeal, he will die over there.” Her son has reportedly received surgery to remove a new melanoma from his back, but afterwards he was quickly returned to his cell, where he shares one shower and two toilets with nineteen cellmates.

Such overcrowding, along with a general disregard for minimum standards laid out in international law, are a familiar feature of reports from inside Iran’s prisons and especially from the wards where political prisoners comprise the majority of the population. Last month, 200 inmates at the women’s ward of Garchak Prison published an open letter affirming that their unsanitary, uninsulated, and poorly ventilated cells were so cramped that many prisoners were forced to sleep on the floor.

The letter’s authors implied that they were planning a hunger strike, in that many had begun refusing their lunch rations, which are often inedible anyway. Hunger strikes are a familiar means of drawing attention to the human rights violations in Iran’s prisons, but they are just as likely to bring about reprisals as they are to prompt a change of behavior by prison officials.

In June, Nazanin Zaghari-Ratcliffe underwent a 15-day hunger strike while Richard Ratcliffe did the same while demonstrating outside the Iranian embassy in Britain. But far from spurring more productive diplomatic discussions of her case, the protest apparently set the stage for a further reduction in her privileges, including phone calls and family visits. The broader consequences of Tehran’s response remain to be seen, but if the crisis surrounding the detained British tanker is any indication, regime authorities are not averse to holding one Western asset accountable for the actions of another.