Suicide by Cop Among Officer-Involved Shooting Cases

Abstract: The frequency and characteristics of suicide by cop cases (SBC) among a large (n = 707) nonrandom sample of North American officer-involved shootings (OIS) were investigated. “Suicide by cop” is when a subject engages in behavior which poses an apparent risk of serious injury or death, with the intent to precipitate the use of deadly force by law enforcement against the subject. Thirty-six percent of the OIS in this sample were found to be SBC with high interrater agreement (intraclass correlation coefficient = 0.93) for category classification. SBC cases were more likely to result in the death or injury of the subjects than regular OIS cases. Most SBC cases were spontaneous, but had clear verbal and behavioral indicators that occurred prior to, and during the event. Findings confirm the trend detected in earlier research that there was a growing incidence of SBC among OIS. SBC individuals had a high likelihood of possessing a weapon (80%), which was a firearm 60% of the time. Half of those with a firearm discharged it at the police during the encounter. Nineteen percent simulated weapon possession to accomplish their suicidal intent. Other findings highlight the histories and commonalities in this high risk group.     

Human cannibalism: a case report

Human cannibal cases are relatively rare in modern civilized societies. We report a single case of familial cannibalism that occurred in Oklahoma in 1977. The investigation posed unique problems in pathology, psychiatry, criminalistics, and serology.     

Sensitivity enhancement of ninhydrin-treated latent fingerprints by enzymes and metal salts

Lyophilized Sigma Type III trypsin has been applied to latent prints two weeks to two months old. This trypsin preparation eliminates the background problems that had been encountered with old prints in a previous study. Zinc chloride treatment of latent prints previously exposed to ninhydrin enhances their detectability upon laser examination. However, it has been reported that the zinc chloride reaction occasionally fails to occur. Accordingly, we have investigated the optimization of this reaction. We find that high humidity and elevated temperature, particularly the former, are needed. Cadmium nitrate, although it produces weaker fluorescence than zinc chloride, may at times be useful. Reaction conditions are much the same as those for zinc chloride.     

The Distribution of Household Property Crimes

Previous studies have established that repeat victimizations occur more frequently than would be expected if households within a particular area were victimized randomly. This implies that characteristics of the household affect the victimization rate. Even controlling for these characteristics, we find that a Poisson model does not capture the distribution of victimizations because repeat victimizations are more concentrated than it would indicate. This leads us to adopt the negative binomial generalization of the Poisson model. Our analysis uses sociodemographic attributes of the household and community-level characteristics to predict victimizations, with the victimization data being the observed number of property crime victimizations from the 1992 British Crime Survey. The negative binomial generalization is found to be highly statistically significant and the crime concentration it implies becomes much more marked as the predicted number of victimizations increases.     

Detection of bullet residue in bone using proton-induced X-ray emission (PIXE) analysis

External beam proton-induced X-ray emission (PIXE) analysis has been used to verify the presence of lead in the finger bone of a murder victim. The deceased, who had been buried several years, was known to have suffered a bullet wound to his right hand several years before death. X-ray radiographs of the right second proximal phalanx revealed the possible presence of metal fragments below the surface of the bone. To verify the presence of lead in a nondestructive manner, the bone was scanned with a 1.5-MeV proton beam. PIXE analysis showed that lead was present only in the vicinity of the fragments previously detected in the radiographs. A study of gunshot residue in bone shows that the distribution of lead around the bullet hole is independent of the firing distance for distances greater than 0.6 m.