Zacarias Moussaoui, who was convicted in 2006 of conspiring with the Sept. 11 attackers, has filed a complaint over the conditions at the federal prison where he is serving a life sentence.

The Associated Press reports that Moussaoui has filed handwritten petitions in federal courts in Oklahoma and Colorado, saying he suffers "psychological torture" as he is kept in complete isolation. Moussaoui seeks relief from prison guidelines that "keep me in total isolation without access to a lawyer to break me psychologically," according to the AP.

The news service says his petitions, which also claim that he has been assaulted while in federal custody, ask for the help of various judicial officials.

Moussaoui was charged with six conspiracy counts related to the Sept. 11 attacks, and his case from arrest to conviction stretched over five years. Prosecutors argued that he should be held responsible for a role in the attacks, which occurred while Moussaoui was already in jail. He had been arrested on immigration charges after arousing suspicion at a Minnesota flight school when he wanted to learn to fly a 747 though he had no pilot's license.

He was allowed to represent himself, though the judge kept his attorneys, with whom Moussaoui did not cooperate, on standby. He pleaded guilty.

Federal prosecutors sought the death penalty. But jurors decided he should receive life in prison instead, with some of them concluding that he played a minor role in the Sept. 11 attacks.

In a 2006 article about Moussaoui's sentencing, The New York Times examined the role of victims' families, some of whom testified for the prosecution, some for the defense:

"Neither group was allowed to testify on their preferences for Mr. Moussaoui's fate. But defense lawyers said they believed that the jurors inferred from their witnesses that some victims were not seeking the death penalty." 'The testimony of family members was immensely personal and also displayed the deep divisions that mark the issue of capital punishment in this country,' [one of Moussaoui's lawyers, Edward B. MacMahon Jr.] said. 'This is, to our knowledge, the only capital case where victims have testified as witnesses called by the defense. This testimony demonstrated resilience and the possibility of renewal.' "

Moussaoui's conviction was upheld by a federal appeals court in 2010, and he now lives out the rest of his days confined at the United States Penitentiary Administrative Maximum Facility in Florence, Colo., known as ADX.

Conditions there are intentionally isolating.

ADX was designed "to control a very small subset of the inmate population who show absolutely no concern for human life," Norman Carlson, then the director of the Federal Bureau of Prisons, told the San Francisco Chronicle in 1998.

Former inmate Travis Dusenbury spent 10 years locked up there.

"It wasn't like any of the prisons I'd been to, and I've been to a lot of prisons. I've been locked up in some isolated, rural places, but at least at those places I could always see a highway, see the sky," he told the Marshall Project in 2016. "But at the ADX, you can't see nothing, not a highway out in the distance, not the sky. You know the minute you get there you won't see any of that, not for years and years."

"It's just the harshest place you've ever seen," Dusenbury said. "Nothing living, not so much as a blade of grass anywhere."

Many inmates at ADX spend 23 hours a day in solitary confinement.

In 2014, Amnesty International published a report on the physical and psychological impact of the conditions at the Supermax prison:

"Symptoms resulting from being held in isolation for extended periods include anxiety, depression, insomnia, hypertension, extreme paranoia, perceptual distortions and psychosis. "The ADX Florence federal facility has a capacity for 490 male inmates. Prisoners spend a minimum of 12 months in solitary confinement before they may become eligible for a reduction in the restrictions of their detention. In reality, many spend much longer in isolation. One study produced by lawyers found the average length of time an inmate would spend in isolation was 8.2 years."Most inmates are held in cells with solid walls and a barred, air-lock style chamber in front of a solid metal door, to ensure they have no contact with other prisoners. One small slit of a window allows them a view of the sky or a brick wall."Furniture in the cells is made of poured concrete and consists of a fixed bunk, desk and a stool, as well as a shower and a toilet. Meals and showers are taken inside the cells and medical consultations, including mental health checks, are often conducted remotely through teleconferencing."

The human rights organization says the use of prolonged solitary confinement at the prison amounts to cruel and inhuman treatment in violation of international law.

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