Human Rights Watch has issued a report stating that mentally ill prisoners are being abused in detention facilities across the US, and that these practices are happening in over 5,000 facilities.

US prison staff use excessive & even malicious force on prisoners with mental disabilities https://t.co/e1HfEUnueCpic.twitter.com/sK3QqDDPjh — Human Rights Watch (@hrw) May 12, 2015

The activist group says inmates are being subjected to unnecessary and excessive use of force, and the problem is widespread.

The report provides details of cases where inmates were shocked with Tasers, and where pepper spray was used against them.

In some cases, prisoners were left in restraint chairs for days, or put in scalding showers.

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“I think the public and legislators for far too long have been willing to send people to prison, without thinking a whole lot about what life behind bars [is like]. And what goes on behind bars is often hidden, people don’t know what is happening,” Jamie Fellner, one of the report’s authors and senior adviser at Human Rights Watch, told RT.

She added that prison authorities “don’t issue monthly reports on how many people they have pepper-sprayed, or how many people have had Tasers used against them.”

“What we wanted to focus on was <…> the fact that in so many cases when force wasn’t required, when you had non-violent, minor non-threatening misconduct by a prisoner that didn’t need to be responded to with force,” Fellner concluded.

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Among the especially troubling cases was Nick Christie, a 62-year-old man who had recently stopped taking his medications for depression and anxiety. He was incarcerated in Florida in 2009 for a nonviolent misdemeanor.

At one point, locked in his cell and crying out for medical help, he kept yelling and banging on the cell door.

Prison officials sprayed him with chemical spray over a dozen times in 36 hours, and immobilized him in a restraint chair with a spit mask covering his face. He died from cardiac arrest.

Another Florida prisoner diagnosed with schizophrenia defecated on the floor of his cell and refused to clean it up.

Officers allegedly put him in a scalding shower, left him there for over an hour, and the inmate subsequently died.

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However, the case that specifically caught the attention of human rights activists was 35-year-old Christopher Lopez. He was diagnosed as schizophrenic and was discovered on his cell floor semi-conscious.

Staff failed to call medics and instead put Lopez in a restraint chair. A few hours later, he experienced a severe seizure.

The officers finally released him from the chair, but left him lying handcuffed on the floor. Lopez died a few hours later. His lawyer spoke to RT about the case.

“His mother had contacted me and said he had died in custody, she went to look at the body and saw signs of abuse. That got me interested, I got hold of the autopsy report, and began to investigate it,” attorney David Lane said.

“What appeared to be the cause of death was an overdose of psychotropic medication to the point of electrolyte imbalance, and his heart was slowly stopping,” he added.

The lawyer also told RT that the general attitude towards mentally ill inmates in the US is that they are a “management problem,” and they are dealt with like this, “as opposed to mentally ill human beings.”

Around 20 percent of prisoners in the US have a serious mental illness, including schizophrenia, bipolar disorder and major depression, according to a press release issued by Human Rights Watch. Inmates suffering from such conditions often find it difficult to cope with imprisonment and to comply with instructions.