Bernard Vernon-Lee Kean, a 52-year-old man, died at Community Hospital of the Valleys in Perris, California, during an overnight intensive-care shift in early April 1981. Published accounts commonly identify his death date as April 4, 1981, although the California Supreme Court's later opinion in the murder case against nurse Robert Rubane Diaz labels Kean's death as April 3. The court record establishes that Kean died at 5:07 a.m.
after a frightening series of seizures, respiratory failure and cardiac arrest.
Kean had arrived at the hospital's intensive care unit at approximately 1:00 a.m. suffering from chest pain and alcohol intoxication. Dr. Gillian DeRaad had examined him in the emergency room and believed he might have suffered a myocardial infarction. When Kean entered the ICU, nurse Lois Cheville described him as intoxicated but alert, agitated and combative. Within about 40 minutes, however, he had fallen into a sound sleep and his heartbeat appeared normal. Robert Diaz, a registered nurse working the night shift, was one of the two nurses caring for patients in the unit.
At approximately 2:10 a.m., Kean abruptly suffered the first of three seizures. Cheville summoned Dr. DeRaad, who ordered several medications, including lidocaine, a drug routinely used to treat dangerous disturbances of the heart rhythm. Diaz administered the medications. Kean initially improved, but his condition deteriorated again at approximately 4:03 a.m., when he suffered another seizure followed by respiratory and cardiac arrest. Medical personnel succeeded in restoring his heartbeat, but Kean never regained consciousness. At about 5:00 a.m. he experienced another seizure, and seven minutes later he was dead.
Because Kean was seriously ill and had significant underlying medical problems, his death was not immediately treated as a homicide. Both prosecution and defense experts would later agree that he suffered from severe heart and liver disease. Evidence indicated that an acute myocardial infarction caused by a blocked coronary artery was a major factor in his death. What eventually transformed Kean's death from an apparently tragic medical event into a murder investigation was the extraordinary pattern developing around him: other patients in the Perris ICU were suffering similarly violent seizures, often immediately followed by respiratory and cardiac arrest. Nurses testified that this was unlike anything they normally saw among cardiac patients.
As suspicious deaths accumulated, authorities began examining patients who had initially been thought to have died naturally. Bodies that had already been buried were exhumed, and investigators obtained tissue samples for toxicological testing. Kean's tissues contained concentrations of lidocaine that prosecution experts regarded as lethal. An initial examination performed in May 1981 found 58 micrograms of lidocaine per gram of liver tissue and 92 micrograms per gram in his kidney. When the tissues were retested in 1983, the results were different but remained extremely high: 75 micrograms per gram in the liver and 83 in the kidney. Prosecution toxicologists maintained that both sets of results demonstrated lethal quantities of the drug.
The medical evidence surrounding Kean's final hours became particularly important. Dr. Dale Isaeff examined electrocardiograph rhythm strips recorded between Kean's later seizures and found an abnormally broad QRS complex, an electrical pattern that prosecutors argued was compatible with severe lidocaine poisoning. Isaeff concluded that Kean's symptoms immediately before his death were consistent with several massive overdoses of lidocaine administered during the night. Pathologist Dr. Rene Modglin and toxicologists Michael Peat, Alphonse Poklis and Randell Baselt also concluded that Kean had received an enormous quantity of the drug shortly before dying. Modglin testified that although Kean's acute heart attack was a primary cause of death, the lidocaine overdose shortened his life.
Diaz consistently disputed that interpretation. His defense argued that Kean had died naturally from his serious heart disease and suggested that the seizures could have resulted from alcohol withdrawal. Defense witnesses also challenged the reliability of calculating a patient's dosage from concentrations of lidocaine remaining in tissue after death. Prosecutors countered that alcohol-withdrawal seizures were unusual while a patient was sleeping, as Kean apparently was when his first seizure developed, and that the exceptionally violent nature of the seizures was inconsistent with the defense explanation. The judge ultimately accepted the prosecution's interpretation, finding sufficient evidence that Kean had been killed through a massive lidocaine overdose.
Kean's death was part of a much larger investigation at Community Hospital of the Valleys. Diaz had begun working the hospital's night shift on March 29, 1981. Over the following three and a half weeks, at least 13 patients working through the night suffered violent seizures, generally followed by cardiac and respiratory arrest, and nine of those patients died. Diaz subsequently worked at San Gorgonio Pass Memorial Hospital in Banning, where another patient died after exhibiting a similar pattern. Investigators eventually concluded that Diaz was the common link between the victims and that massive injections of lidocaine had been used to produce the fatal crises. No prosecution theory established that Kean or the other victims had been selected because of anything they had personally done; the state never established a definitive motive for the series of killings.
The investigation was extensive and initially ranged beyond Kean and the eventual murder victims. Authorities examined dozens of suspicious deaths at hospitals where Diaz had worked. Community Hospital of the Valleys itself came under scrutiny over its operation and patient care, and California officials eventually suspended the hospital's license. On May 1, 1981, investigators searched Diaz's home. According to later accounts of the investigation, lidocaine was among the medical material discovered there, while toxicological examinations of the dead patients continued for months.
Diaz was finally arrested without incident at his Apple Valley home on November 23, 1981. He was accused of murdering 12 hospital patients. California formally filed a complaint on December 23 charging him with 12 counts of murder and seeking the death penalty. Eleven of the charged deaths occurred at Community Hospital of the Valleys in Perris and the remaining charged death occurred at the hospital in Banning. Bernard Kean was one of the victims specifically included in the case against Diaz.
Diaz pleaded innocent and maintained that he had not poisoned the patients. His defense challenged the toxicology, emphasized the victims' serious existing illnesses and argued that natural disease or legitimate medical treatment could account for the deaths. Prosecutors presented a circumstantial case built from toxicology results, unusual seizure patterns, electrocardiograph evidence, Diaz's access to the patients and medications, and the fact that he was present during critical periods surrounding the deaths. Evidence concerning another patient, Estel Lee Jones, who died at a different hospital while Diaz was working, was also introduced even though Diaz was not charged with Jones's murder in Riverside County. Prosecutors used that death to reinforce their contention that the same distinctive method had followed Diaz from hospital to hospital.
Diaz waived his right to a jury, leaving Riverside County Superior Court Judge John H. Barnard to determine guilt. The nonjury trial began on October 31, 1983, and lasted for months as doctors, nurses, toxicologists and other experts testified about the medical evidence. On March 29, 1984, Barnard found Diaz guilty of all 12 counts of first-degree murder, including the murder of Bernard Kean. The judge also found the multiple-murder special-circumstance allegations to be true.
On April 11, 1984, Judge Barnard rejected the defense request for life imprisonment without parole and sentenced Diaz to death in California's gas chamber. Prosecutor Patrick Magers emphasized that Diaz had occupied a position of extraordinary trust, caring for patients who were dependent on him for their survival. Despite the convictions, prosecutors never proved a definitive motive for why Diaz killed Kean and the other patients. The California Supreme Court later reviewed the case, ordered 11 repetitive multiple-murder special-circumstance findings stricken on technical grounds, but otherwise affirmed the judgment and the murder convictions. Diaz remained under a death sentence and ultimately died in prison in 2010 without being executed.
