Attorneys for a non-profit legal group in Chicago have filed a motion in a downstate court case involving whether the supermax Tamms prison should close, asking the judge to hear testimony from prisoners held there for years in solitary confinement.

Alan Mills and Nicole Schult, lawyers for the Uptown People's Law Center, argue in a written motion that Associate Judge Charles Cavaness should allow testimony that the inmates have been psychologically damaged by continuous solitary confinement, which for some has entered the 15th year.

The lawsuit in Alexander County in the southern tip of Illinois where the prison is located, was filed by attorneys for the American Federation of State, County and Municipal Workers, a union which represents guards. The union contends that closing the supermax on Aug. 31, as Gov. Pat Quinn has proposed for budgetary reasons, would increase violence throughout the 45,000-inmate state prison system by removing a deterrent to violent behavior. The prison holds fewer than 200 inmates.

Activists, including the Tamms Year Ten committee, have long argued that the solitary-only Tamms prison psychologically damages inmates, including those who are mentally ill.

The Chicago law center's brief cites a 2010 ruling by U.S. District Court Judge G. Patrick Murphy in an unrelated case. Murphy wrote, "Tamms imposes dramatic limitations on human contact, so much so as to inflict lasting psychological damage and emotional harm on inmates confined there for long periods..."

Cavaness earlier ruled that the law center had no standing in the civil case before him.

Schult said Tuesday that the motion asks Cavaness to reconsider his previous ruling on the basis of prior legal decisions that, according the center's argument, inmates would be affected by the outcome of whether Tamms closes or remains open.

It is unclear whether Cavaness has the authority to reverse Quinn's decision to close Tamms. An attorney for the governor's office has argued that the decision to close is a political matter that should not be decided in court.

Both sides have agreed to temporarily suspend the transfer of Tamms inmates to other maximum security prisons and to meet with a state arbitrator to discuss the issues.

The next court hearing is set for Aug. 31.