The settlement resolves a federal lawsuit that followed a four-year investigation that revealed numerous flaws in the mental-health-care system, according to DOJ officials. Tuesday's settlement gives the state five years to make "extensive" reforms in the system, officials said.

"(The investigation) showed significant deficiencies in patient care and in the conditions in which the patients were housed," said Thom Mrozek, a DOJ spokesman in Los Angeles. "The settlement filed in court will dramatically improve patient care and housing conditions by, among other things, increasing staffing levels, improving staff training, improving the use of medications and implementing a new framework for diagnosing and treating patients."

The agreement is set to be filed in the United States District Court for the Central District of California.

The Justice Department launched its investigation in 2002 with a review of Metropolitan State Hospital in Norwalk. DOJ officials followed that with a January 2004 investigation into Napa State Hospital, and subsequent probes at Patton in April 2004 and Atascadero State Hospital in February 2005.

Patton and Atascadero, are not officially part of the settlement, Mrozek said, because the required documentation in each hospital's case has yet to be completed. Because the settlement requires improvements statewide, however, Patton and Atascadero will benefit, he said.

Patton officials were not available for comment late Tuesday.

The DOJ's investigations revealed significant civil-rights violations that included a pattern of preventable suicides and serious, life-threatening assaults on patients by staff and other patients, officials said. In two instances, officials found patients were slain by other patients.

This year at Patton, for example, Shane Williams, 28, was found hanging from the locker door in his bedroom.

Care provided at the hospitals departs substantially from generally accepted professional standards, officials said, and patients are not served in the settings most appropriate to their needs, nor are requirements of court-ordered confinement followed.

The state agreed to address and correct all of the violations identified by the DOJ, federal officials said.

"We hope that these improvements will serve as a model for other government-operated hospitals around the nation," Mrozek said. "And the experts that have been assisting us with this believe that it will."