Georgia promised the federal government Thursday it will make dramatic improvements in its state psychiatric hospitals - and that it will spend what's necessary to protect patients from harm.

The pledge, signed late in the day by Gov. Sonny Perdue, commits the state to a five-year plan of correcting deficiencies that caused hundreds of patient injuries and illnesses and dozens of deaths.

In reaching a settlement agreement with the U.S. Justice Department, the state did not admit wrongdoing.

But officials did not dispute the conclusions of federal investigators that the seven state hospitals have repeatedly violated patients' constitutional rights by failing to keep them safe, providing incompetent medical care, and conducting shoddy investigations into suicides and other deaths.

"When a state undertakes to care for persons with mental illness and developmental disabilities, it accepts responsibility to protect them from harm," Grace Chung Becker, acting assistant attorney general for the Justice Department's Civil Rights Division, said in a statement.

"I think it's a very positive outcome," Gwen Skinner, head of the state's mental health division, said in an interview. "I think we'll get a better system for it."

The Justice Department launched an investigation into the state hospitals in April 2007, responding to articles in The Atlanta Journal-Constitution that revealed widespread horrors in the hospital system: unnecessary patient deaths, abuse by hospital workers, overuse of medications to sedate patients, the discharge of patients to homeless shelters and street corners, and inadequate investigations conducted by the same agency that operates the facilities.

The newspaper reported that at least 136 patients died under suspicious circumstances from 2002 through late 2007.

The Justice Department last year concluded that the hospitals' failure to address critical errors caused unnecessary deaths, injuries and illnesses.

The settlement agreement, which requires a federal judge's approval, binds the state to "undertake its best efforts" to find enough money to transform the hospitals. If legislators fail to allot the money, federal authorities may ask a judge to force additional spending.

State officials have not determined how much compliance will cost. A Journal-Constitution analysis last year found that increasing mental health spending in Georgia to the national average would require more than doubling the current annual budget of about $465 million.

Perdue sought no new spending on psychiatric hospitals in the state spending plan he offered this week to the General Assembly, according to advocates for people with mental illness. The governor asked lawmakers to make widespread spending cuts across state government to close a $2 billion budget deficit.

But after Perdue signed the settlement agreement, his spokesman, Bert Brantley, said, "The improvement of care will result in additional investments - more staff, the things you would expect."

Skinner, the mental health chief, said the state would have to provide adequate hospital staffing, enhance employee training and bring in experts to design a better system of care.

"Some of those things are going to cost money," she said. "Some of them won't."

Regardless, the settlement agreement gives the state one year to correct conditions that have caused most of the patient deaths. The state agreed to improve efforts to prevent suicides, choking deaths and patient-on-patient assaults.

Within four years, the state must make demonstrable improvements in medical and nursing care and discharge planning, and must show that the hospitals restrain or seclude patients as little as possible.

Federal authorities will re-inspect hospitals at least twice to monitor the state's progress, the settlement agreement says. In addition, state officials agreed to submit compliance reports in six and 12 months and then once a year. The agreement also requires the state to promptly notify the Justice Department of every patient death and to turn over investigative reports, including autopsies, in each case.

The governor's office and the Justice Department announced the settlement five days before the change in administrations in Washington, and the same day that several advocacy groups asked U.S. Attorney General Michael Mukasey to reject a "premature" agreement.

The groups cited chronic underfunding of Georgia's mental health system, as well as the state's push to close some of its psychiatric hospitals and to contract with private companies to operate others.

"Organizational changes alone, as Georgia has proposed so far, are not enough," the advocacy groups said. "DOJ may be our last hope to help move our systems back to acceptable quality."

Even as federal and state officials negotiated a settlement agreement in recent weeks, the Justice Department investigation continued. Late Thursday, it released a letter to Perdue, sent earlier in the day, that detailed "significant and wide-ranging deficiencies" at Northwest Georgia Regional Hospital in Rome.

The letter was a stark reminder of the depth of work facing state officials.

"We found a troubling number of incidents in which [the hospital] failed to recognize signs of suicide risk and failed to take appropriate action," the letter said.

The hospital, with chronic staffing shortages, often used medications to control behavior or as a chemical restraint, rather than to treat psychotic symptoms, investigators found.

The letter also cited "numerous instances" when patient assaults on other patients resulted in serious injury. Investigators said some serious incidents, including a suicide attempt, were never reported or investigated by the hospital.