LINCOLN - Lawyers for the state are pushing back on allegations in a federal lawsuit that conditions in the overcrowded state prison system deny inmates their right to decent health care and living conditions.

In a 108-page brief filed Tuesday, state attorneys maintain that the Nebraska Department of Corrections has increased investment in facilities and employees, provides "excellent" access to health care and is on a path to reduce overcrowding.

Overall, there may be "problems" in the state prison system, but the department has been addressing them, according to Assistant Nebraska Attorney General Ryan Post, the lead attorney defending the state. "We obviously don't believe they're constitutional violations," Post said.

The ACLU of Nebraska filed a federal civil rights lawsuit in 2017, alleging that prison inmates are subjected to cruel and unusual punishment because of inadequate health and mental health care, overuse of solitary confinement and lack of adequate accommodations for handicapped inmates.

The lawsuit has progressed to the point at which a judge must make a key decision about whether it should be a class-action lawsuit - which would encompass all 5,400 inmates in the state and involve much bigger ramifications - or should be limited to the 10 prisoners initially named in the ACLU filing. That ruling is not expected until the end of the year.

State lawyers, in a motion Tuesday, asked the U.S. District Court to deny the ACLU's recent request to certify its lawsuit as a class action.

ACLU Director Danielle Conrad, in a statement, said it was "disappointing but unsurprising that the Attorney General continues to distort undisputed facts and utilize delay tactics while Nebraska prisons remain mired in crisis." There is no dispute, she said, that Nebraska's prison system is the second-most overcrowded system in the country and that inmates face inhumane and unconstitutional conditions.

But Post told reporters Tuesday that the lawsuit isn't about overcrowding but instead is about whether the department has shown "deliberate indifference" in providing health and mental health care to inmates.

Experts hired by the state, according to the brief, said Nebraska offers "excellent" access to health care for inmates and was not "haphazard or understaffed," as the ACLU claims, in offering mental health services.

The brief outlined nearly 50 steps that have been taken to address staff vacancies at prisons and said that when construction of a couple of new prison additions is completed, the prison system should be at only 103% of "operational capacity" by the year 2022.

State lawyers also asked the court to consider "operational capacity" as another metric in measuring overcrowding in the lawsuit, along with "design capacity," which is how overcrowding has been measured in the state. Design capacity compares the number of inmates with the available prison beds, while operational capacity measures how many inmates can be fed and supervised in a given facility.

Nebraska prisons have been over 140% of design capacity - a benchmark used by federal courts in the past overcrowding lawsuits - for over a decade, despite recent efforts to reduce crowding through sentencing reform and greater use of probation and parole. The new prison expansions would include construction of a huge cafeteria and medical facility, which the brief said would dramatically increase the operational capacity.

World-Herald staff writer Rick Ruggles contributed to this report.