The conditions exacerbate symptoms in many prisoners, the suit alleges, and lead to sleeplessness, hallucinations, paranoia, and self-destructive urges, which are often interpreted by prison staff as misbehavior.
"The result is a Dickensian nightmare in which many prisoners, because of their mental illness, are trapped in an endless cycle of isolation and punishment, further deterioration of their mental illness, deprivation of adequate mental health treatment, and inability to qualify for parole," the lawsuit states.
The Department of Corrections does not comment on pending litigation, said press secretary Susan McNaughton.
As of December, about one-third of the 2,400 prisoners in the state's restrictive housing units had been diagnosed with mental illnesses, according to the lawsuit.
The suit asks the court to order an end to the policies in question and other injunctive relief.
Robert Meek, an attorney with the Disability Rights Network, said many people live for years with serious mental health issues before landing in prison. There, the trauma of being incarcerated causes many to lash out.
"They'll end up getting written up, punished over and over, and some will spend years in solitary," he said.
Inmates in restrictive housing units have less access to rehabilitative programs, according to the suit, and have contact only with a cellmate or member of the prison staff. The sensory deprivation can cause fear, and some inmates refuse to leave their cells for weeks or months, even for exercise or showers.
"It causes a tremendous amount of harm," Meek said.
In the 1800s, solitary confinement was viewed as a positive model for inmates. Its use was pioneered by Philadelphia's Eastern State Penitentiary. Prominent city officials and others believed that criminals, if isolated, would be more inclined to reflect on their misdeeds and gradually become reformed.
But research has demonstrated that prisoners who spend prolonged periods of time in solitary confinement are mentally ravaged. Additionally, it costs more to hold a prisoner in solitary confinement, and several states have taken steps to end the practice. Advocacy groups have filed similar lawsuits in Virginia, Colorado, Indiana, and New Mexico.
Contact Allison Steele at 610-313-8113 or asteele@phillynews.com