In Canada, it’s called the Special Handling Unit. Most prisoners know it as the SHU, or by its colloquial titles, such as “the hole” or “the hotbox”. It’s a tactic reserved for prisoners that are deemed particularly dangerous or threatening, and its prevalence is increasing. Between 2010 and 2013, the number of inmates admitted to the SHU per year rose from 8,000 to 8,600, and experts expect that this number will continue to grow.

But solitary confinement is more than a punishment. It’s a form of psychological torture. For between 22 and 24 hours a day, prisoners are confined to bleak, unfurnished cells for months — sometimes years — on end. They are often denied access to TV or even radio, and are isolated from other prisoners. Most inmates in solitary confinement are allowed a limited supply of books, a bar of soap, photographs of friends and family members, tools for writing, and little else. Some cells lack windows, and virtually all of them are under constant video surveillance.

Ingoing and outgoing mail is heavily monitored. Visits from friends and family — if they are allowed at all — are aggressively surveilled and devoid of any physical contact. The cells themselves range from about 60 to 80 square feet, and the concrete “yards” in which prisoners are allowed to exercise for approximately an hour each day are rarely much larger.

Ironically, solitary confinement was originally envisioned as a humane alternative to the sadistic prison conditions of yesteryear. Social activists of the time – Quakers and Calvinists chief among them – saw solitary confinement as a more ethical alternative to the  rotting, overcrowded jails and Hammurabian “eye for an eye” punishments of the day. They were the first to consider the prison system as a potential conduit for rehabilitation, and the Walnut Street Jail, built in Philadelphia in 1790, was the first prison to resemble our modern institutions.

Most inmates in solitary confinement are allowed a limited supply of books, a bar of soap, photographs of friends and family members, tools for writing, and little else.

Expanding on their revolutionary idea of isolation as punishment, Eastern State Penitentiary was established in 1829 as the first jail made entirely of solitary cells. But despite noble intentions, the system was quickly revealed to have unintentional effects. Prolonged periods of solitude led inmates to such ends as psychosis, anxiety and suicide.

By 1890, over a century after Walnut Street Jail first opened its doors, the United States Supreme Court condemned the practice of solitary confinement. Inspired by a wealth of medical evidence from around the world, they stated: “A considerable number of prisoners fell, after even a short confinement, into a semi-fatuous condition . . . others became violently insane, others, still, committed suicide, while those who stood the ordeal better were not generally reformed.”

But in the recent past, solitary confinement has regained popularity. According to The Globe and Mail, about 850 of the 14,700 prisoners in federal Canadian prisons are in the SHU. Our neighbour to the south is no better: over 80,000 prisoners are held in solitary confinement in the United States at any given time, the highest percentage of any democratic nation.

Inmates are chosen for solitary confinement based on a wide variety of criteria. Prisoners who are considered at risk of violence from other inmates, such as pedophiles or witnesses, are held in the SHU as a form of protective custody. Super-maximum security prisons – better known as “supermax” prisons – are composed of almost entirely SHU cells.

Prisoners are also put into solitary confinement based on their alleged connections to prison gangs. Many of these connections are tenuous at best — leftist literature and writings on prison rights can be considered sufficient evidence for incarceration, as well as unverified accusations of gang affiliation from prison informants.

One of the most infamous supermax prisons in North America is Pelican Bay State Prison, located just outside Crescent City in California. Of the 1,126 prisoners held in the prison’s SHU, over half have been in solitary confinement for at least five years; over 78 of those inmates have been confined for more than 20.

Having been put in solitary confinement in an Iranian prison himself, photojournalist Shaun Bauer’s investigation of Pelican Bay in 2012 is eye-opening. He describes the cells in the prison as smaller than the one he was confined to for 26 months. His had a window, whereas the rooms in Pelican Bay do not.

All of the gang validation proceedings — that is, the system through which the prison’s gang investigator makes his case for a prisoner’s involvement — are internal, with no judicial involvement. Of 6,300 validations submitted to Sacramento for approval in the past four years, only 25 were rejected. Only the gang investigator and the inmate are present during the sentencing.

Bauer’s report is not only remarkable due to his unique experience with solitary confinement — it is one of the few available reports of its kind. There is an absence of accurate statistics concerning many supermax prisons in the United States and Canada. As Debra Parkes, a University of Manitoba law professor, told The Globe and Mail, “There are no meaningful mechanisms for accountability in provincial and territorial corrections. . . . We essentially have no idea what goes on inside them.”

Although information concerning the treatment of Canadian prisoners in solitary confinement is troublingly sparse, there is little doubt about the psychological effects of the process. According Terry Kupers, a psychiatrist at the Wright Institute, “What we’ve found is that a series of symptoms occur almost universally. They are so common that it’s something of a syndrome.”

Stuart Grassian, one of the most prominent specialists in this field of study, has referred to this disorder as the “SHU syndrome”. Grassian described symptoms like increased sensitivity to stimuli, hallucinations, memory loss, and impulsiveness as resulting from prolonged periods in solitary confinement.

Craig Haney, a professor of psychology at the University of California, has included headaches, chronic fatigue, heart palpitations, chronic depression and violent fantasies as potential symptoms. Roughly half of all prison suicides occur in solitary confinement.

“People who have been in long-term solitary confinement almost inevitably emerge with major impairments in their ability to cope with the larger world and the larger community,” Dr. Grassian told The Globe and Mail.

Canadian prisons have also seen a rise in violence within the past decade: between 2007 and 2012, the population of Canada’s prison gangs rose from 1,421 to 2,040, according to CBC News. This rise correlates with the rise of solitary confinement tactics. But these tactics only serve to separate gang members from each other, rather than rehabilitate them as contributing members of society.

After all, prisoners in solitary confinement have no access to prison programs and treatments. Even if these tactics are successful in segregating gang members and reducing rates of violence in prisons – rates that have been climbing steadily within the past five years – those prisoners who eventually see the other side of a jail cell are often incapable of re-assimilating into Canadian society.

Considering the presumably well-intentioned beginnings of the practice, we have to ask ourselves: is solitary confinement ethical?

The United Nations defines torture as “any act by which pain or suffering, whether physical or mental, is intentionally inflicted on a person for such purposes as . . . punishing him for an act he or a third person has committed or is suspected of having committed, or intimidating or coercing him or a third person, or for any reason based on discrimination of any kind, when such pain or suffering is inflicted by or at the instigation of or with the consent or acquiescence of public official or other person acting in an official capacity.”

Juan E. Méndez, the United Nations Special Rapporteur on torture, has spoken out in favour of banning the practice altogether. “Considering the severe mental pain or suffering solitary confinement may cause, it can amount to torture or cruel, inhuman or degrading treatment when used as a punishment,” he told the UN General Assembly in 2011. “Indefinite and prolonged solitary confinement, in excess of 15 days, should also be subject to an absolute prohibition.”

The Optional Protocol to the Convention against Torture is a treaty that would allow a subcommittee of the United Nations to perform routine investigations into the places where “people are deprived of their liberty”, in order to ensure that no torture is taking place. As of this article’s publication, Canada and the United States have yet to ratify this protocol.

We have to ask ourselves: is solitary confinement ethical?

But what about those prisoners who pose a threat to correctional officers and their fellow prisoners? “There will always be a few inmates who simply prove too dangerous to be in the general population,” says Jamie Fellner, the senior counsel for the United States Program of Human Rights Watch, an organization which advocates for the preservation of human rights.

“For them, some form of segregation may be the only option. But even then, the nature of segregation should be rethought. No one should be confined in small, empty cells with nothing to do – and no one to talk to – day in and day out, year in and year out.”

This thought is echoed in the recent hunger strike taking place in California prisons. Beginning on July 8, 2013 and the hunger strike reached its 50 day mark last Monday and, at time of publication, is ongoing. It is the largest hunger strike in California’s history. Originating as a protest towards the harsh conditions of Pelican Bay’s SHU, it has spread to several other Californian prisons. An estimated 400 prisoners have participated in the strikes; one of the participants has since committed suicide.

Among the prisoners’ demands are to “end group punishment and administrative abuse,” “expand or provide constructive programming and privileges for SHU inmates”, and “provide adequate nutrition and food.” They have also demanded that prisons “abolish the debriefing policy and modify gang status criteria.”

Debriefing is the most common means through which inmates escape solitary confinement. Prisoners are persuaded into offering incriminating information about their fellow inmates to correctional officers. Prisoners argue that this process places inmates in unnecessary danger, and leads to them being targeted as “snitches.”

Jeffrey Beard, the secretary for the California Department of Corrections and Rehabilitation, has characterized the strikes as a “gang power play.” In a recent op-ed for the Los Angeles Times, he vilifies and dehumanizes the inmates participating in the protest: “Many of those participating in the hunger strike are under extreme pressure to do so from violent prison gangs, which called to strike in an attempt to restore their ability to terrorize fellow prisoners, prison staff and communities throughout California.”

But Beard’s article refused to acknowledge the tortuous and dehumanizing conditions of solitary confinement in North American prisons. In an article by Angela Y. Davis for The Sacramento Bee, she calls the strike “a courageous call for the California prison system to come out of the shadows and join a world in which the rights and dignity of every person is respected.”

If there ever was a time for the United States and Canada to reevaluate their use of solitary confinement as an ethically acceptable form of punishment for prisoners, it is now. The California prison strike only serves to highlight something that many of us already know, but choose to ignore: that solitary confinement is still in widespread use in North America, despite being considered torture by Amnesty International, the United Nations, and the majority of the free world.

Fyodor Dostoevsky once said in his novel The House of the Dead that “The degree of civilization in a society can be judged by entering its prisons.” We must consider the way in which we treat our prisoners in North America, whether or not they are violent, whether or not they are gang members. Our prisons are intended as a means of keeping inmates safe and rehabilitating them, but solitary confinement does neither.