(CN) - California must reduce its prison population by as many as 55,000 inmates in order to provide a constitutionally acceptable level of medical and mental health care, a three-judge panel ruled tentatively on Monday.
"There are simply too many prisoners for the existing capacity," the panel wrote. California's prison system, with more than 150,000 inmates, is the nation's largest.
Gov. Arnold Schwarzenegger declared a state of emergency in 2006, saying the cramped conditions create "substantial risk to the health and safety of the men and women who work inside these prisons and inmates housed in them."
The judges agreed that overcrowding is clearly a problem that poses significant risks.
But inmates and local governments disagree on whether overcrowding is the "primary cause" of the state's inability to provide constitutionally adequate medical and mental health care to prisoners.
The panel said the evidence offered at trial "overwhelmingly" pointed to overcrowding as the main cause of most unconstitutional conditions. The judges cited staff and facility shortages, including the use of triple bunks in gymnasiums and other areas not meant to house inmates.
The panel suggested that California reduce its prison population by shortening sentences, awarding good-behavior credits and reforming parole.
The judges noted that the governor supports measures to reduce the prison population by about 40,000 inmates, saying, "We cannot believe that such support would exist if the adoption of such measures would adversely affect public safety."
They added that the reductions would save $803 million to $906 million a year in prison costs for a state with a $42 billion budget deficit. And even if California plowed some of the savings into new investments and programming, the state would still save between $561 million and $684 million a year.
The judges also signaled support for a prison population cap of 125 percent to 145 percent of designed capacity. In August 2008, the state's prisons were operating at double the designed capacity.
California Atty. Gen. Jerry Brown vowed to appeal the ruling if it's made final.
The three-judge panel consisted of 9th Circuit Judge Stephen Reinhardt, U.S. District Judge Lawrence Karlton and U.S. District Judge Thelton Henderson.