A federal judge in Sacramento is set to hear arguments Wednesday over Gov. Jerry Brown's push to regain state control of inmate mental health care after 18 years of federal oversight and billions of dollars spent to improve treatment.

Lawyers representing the state argue that California is now providing a constitutional level of care to its prison inmates, while attorneys for the inmates say more improvement is needed.

California has spent more than $1 billion in construction for mental health facilities and increased salaries to hire more and better mental health workers. It now has more than 1,700 psychiatrists, psychologists, therapists, social workers and nurses to treat more than 32,000 mentally ill inmates, or about one specialist for every 19 patients.

"California has invested tremendous amounts of money, resources and effort to transform its prison mental health care system into one of the best in the country," the state said in one of its recent court filings.

Inmates' attorneys say the efforts so far are not enough and that more mental health facilities must be built and staffed. They also say more must be done to reduce a suicide rate that exceeds the national average for state and federal prisons.

California's prison suicide rate was 24 per 100,000 inmates in 2012. That compares to 16 per 100,000 inmates in other state prisons and the historical average of nine suicides per 100,000 inmates in federal prisons.