The case series included two homicides and seven accidental deaths. Of the accidental deaths, four were caused by asphyxia, three by restraint devices, one by scald burns, one by airway obstruction without an attempt to resuscitate the victim, and one by hypothermia. With one exception, all patients were at least 80 years old. Eight of the nine patients displayed chronic, incapacitating central nervous system pathology. Of the three accidental deaths involving chest restraints, the restraint was either improperly applied or in disrepair and ligature asphyxia ensued. In two cases, the restraint had been placed backward on the patient; in another case, the bottom of the restraint was missing and this allowed the patient to slip down in his chair. Concealment of evidence was found in one homicide and three accidental deaths. Fearing criminal or civil proceedings, nursing home personnel may attempt to conceal homicidal or accidental deaths in nursing home residents. Because of the serious, chronic illnesses suffered by these patients, attending physicians are often willing to sign death certificates without personally investigating the circumstances surrounding the patient's demise. The authors contend that unnatural deaths of nursing home patients are significantly underreported and that attending physicians and death investigators should investigate sudden deaths more fully. 8 references and 1 table (Author abstract modified)