Accuracy of eyewitness identification is significantly associated with performance on a standardized test of face recognition

OBJECTIVES: This study assessed the relationship between Eyewitness Accuracy regarding a person met under conditions of high stress and performance on a standardized, neutral test of memory for human faces. METHOD: Fifty-three U.S. Army personnel were exposed to interrogation stress. Forty-eight hours later, participants were administered the Weschler Face Test and then asked to identify the one interrogator who they had encountered 48 h earlier. RESULTS: A significant positive relationship was observed between performance on the Weschler Face Test and performance on the Eyewitness task. Inaccurate eyewitnesses exhibited more False Negative errors when performing the Weschler Face Test. DISCUSSION: Trait ability to remember human faces may be related to how accurately people recall faces that are associated with highly emotional circumstances. Detection probability methods, such as ROC curve analyses, may be of assistance to forensic examiners, the police, and the courts, when assessing the probability that eyewitness evidence is accurate.     

Validation of the barcoding gene COI for use in forensic genetic species identification

The application of forensics to wildlife crime investigation routinely involves genetic species identification based on DNA sequence similarity. This work can be hindered by a lack of authenticated reference DNA sequence data resulting in weak matches between evidence and reference samples. The introduction of DNA barcoding has highlighted the expanding use of the mtDNA gene, cytochrome c oxidase I (COI), as a genetic marker for species identification. Here, we assess the COI gene for use in forensic analysis following published human validation guidelines. Validation experiments investigated reproducibility, heteroplasmy, mixed DNA, DNA template concentration, chemical treatments, substrate variation, environmental conditions and thermocycling parameters. Sequence similarity searches using both GenBank BLASTn and BOLD search engines indicated that the COI gene consistently identifies species where authenticated reference sequence data exists. Where misidentification occurred the cause was attributable to either erroneous reference sequences from published data, or lack of primer specificity. Although amplification failure was observed under certain sample treatments, there was no evidence of environmentally induced sequence mutation in those sequences that were generated. A simulated case study compared the performance of COI and cytochrome b mtDNA genes. Findings are discussed in relation to the utility of the COI gene in forensic species identification.     

Incapacitation: Revisiting an Old Question with a New Method and New Data

We use the National Longitudinal Survey of Youth 1997 to obtain estimates of the number of crimes avoided through incapacitation of individual offenders. Incarcerated individuals are matched to comparable non-incarcerated counterparts using propensity score matching. Propensity scores for incarceration are calculated using a wide variety of time-stable and time-varying confounding variables. We separately analyze juvenile (age 16 or 17) and adult (age 18 or 19) incapacitation effects. Our best estimate is that between 6.2 and 14.1 offenses are prevented per year of juvenile incarceration, and 4.9 to 8.4 offenses are prevented per year of adult incarceration.

Smallpox vaccination and the limits of governing through contagion in the Straits Settlements, 1868–1926

Vaccination involves the encounter of nonhuman biological matter and human bodies, recalibrating our susceptibility to illness and death. This boundary-crossing act has been caught in conflicting webs of moral significance, including the normalizing frameworks of public health governance and its corresponding forms of resistance. Such tensions and dynamics were a feature of smallpox vaccination - the first modern, systematic state-driven project to build population immunity. Focusing on smallpox vaccination in the British-ruled Straits Settlements (Singapore, Penang, and Malacca) between 1868 and 1926, we examine the recurrent features of contentions over vaccination from the tentative beginnings of the 1868 Vaccination Ordinance to the systematic extension of vaccination in the 20th century. Engaging science and technology studies of nonhuman agency and social theories on security, we argue that such contentions demonstrate the limits of a power formation we call governing through contagion (GTC). GTC centralizes law and other technologies to normalize public health measures that combat contagious diseases, while dysconnecting populations by its strategies of control. Our history of smallpox vaccination reveals: (i) GTC relies on the interconnectedness of human and nonhuman actors in protecting populations against viral threats; law is essential but does not necessarily drive vaccination or other strategies of control and (ii) resistance to GTC, in which law plays an integral role, reinforces inequalities and differentiated treatment, what we term endemic inter/dysconnectedness.