or years, state officials have tolerated squalid conditions in the privately run "adult homes" that house thousands of mentally ill patients in New York State. In theory, these homes were supposed to provide a humane refuge for the mentally ill after the state began to close its huge mental hospitals decades ago and transfer the patients to settings in the community. But in practice, as documented in a yearlong investigation by the Times reporter Clifford Levy, many homes are a threat to the health and safety of their patients. The lax oversight exercised by a succession of governors and legislatures reflects at best a callous indifference and at worst a knowing and cynical effort to keep state health costs low at the expense of a population with no clout to demand better treatment.

The conditions described by Mr. Levy in a three-part series that ends today are appalling. Dead patients have been left in their rooms for days until the stench became impossible to ignore. Patients have died from ailments they might have survived with proper care. Suicidal patients have thrown themselves from windows lacking safety guards. A violent inmate was allowed to carry a knife that he used to kill his roommate.

The care provided is often rudimentary or nonexistent. Poorly paid, even illiterate workers dispense complex medicines. Operators and doctors have taken patients to medical mills for unneeded treatment or even surgery to earn Medicaid and Medicare billings. To fool inspectors, at one home, workers were ordered to forge psychiatric evaluations and invent treatment programs for patients who never got treatment.

This is not what was intended when the state began to empty its mental hospitals. Many of these homes are worse than the hospitals they replaced. The state has saved a bundle of money by closing its mental hospitals and shifting the burden of paying for mental health care to federal programs. The least it can do is assure that the privately run homes are properly managed.

There is plenty of blame to go around. The State Department of Health, which regulates these institutions, has been slow to investigate problems or respond to its own inspection reports. The State Office of Mental Health, which supervises the mental health care provided but not the homes themselves, might better monitor the institutions as well. The homes clearly need more and better qualified staff, capable of dealing with mental illness. Gov. George Pataki and the legislative oversight committees need to step in and find a way to resuscitate these failing institutions.