Editor’s note: This case depublished by the Supreme Court on 6/13/01 (S095974) Results of a positron emission tomography (PET) brain scan may be properly excluded under People v. Kelly (1976) 17 Cal.3d 24. Appellant here was convicted of first degree murder and allegations of robbery, special circumstances, and use of a deadly weapon were found true; he was sentenced to LWOP. The victim had been bludgeoned in the head with a hammer and then the crime scene was cleaned and staged to make it look like the victim was watching television. At trial, the defense proffered the testimony of an expert in the field of PET scan imaging to show appellant had prior traumatic brain injury which would have adverse affects on his judgment and emotional stability, including blackouts and loss of contact with reality, especially when under the influence of drugs. A PET provides images of metabolic activity in the brain. Prosecution experts testified that the use of PET scans to diagnose or evaluate head trauma remote in time was investigational only and had not been accepted in the neurology and brain imaging field. The trial court therefore properly excluded the evidence because appellant failed to show that the use of PET scans was generally accepted in the science community. In order to establish general acceptance, he had to demonstrate a substantial agreement and consensus of a cross-section of the relevant scientific community (People v. Leahy (1994) 8 Cal.4th 587, 607, 611.) This he did not do.
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