Oral and skin microbiome as potential tools in forensic field

The interest in the analysis of the human microbiome for personal identification purposes is based on the microbial diversity amongst individuals. The oral cavity hosts one of the most diverse and abundant microbial communities in the human body; the skin instead is a complex living ecosystem with unique microbial niches at different sites. Both skin and oral microbiomes are highly individual and relatively stable over time. As saliva and skin debris are often found at crime scenes, the analysis of their microbiome may represent a potential tool for personal identification. However, there are some gaps in knowledge on how factors such as age, sex, geographic origin, diet and pathologies can affect the composition of the microbiome. The aim of this study is to improve the existing knowledge by examining oral and skin microbiomes from the same individuals and evaluating the variability between anatomical sites and donors. For this study, 50 individuals living in Italy donated oral swab samples and provided information regarding their diet, lifestyle, health status, antibiotic use, and other demographic data. Skin swabs from 11 of the 50 individuals were also analysed and compared to the oral swabs from the same donors. All analyses were done through metabarcoding of the 16S rRNA region of DNA extracted from the samples. This research outlines the potential use of oral and skin microbiome signatures as added evidence in personal identification, providing useful investigative clues for future forensic caseworks.     

Molecular identification of forensically important fly species in Spain using COI barcodes

Species identification with DNA barcodes has been proven to be effective on different organisms and, particularly, has become a routinely used and quite accurate tool in forensic entomology to study necrophagous Diptera species. In this study, we analysed 215 specimens belonging to 42 species of 17 genera, from 9 different Diptera families. Flies were collected in 39 Spanish localities of the Iberian Peninsula sampled across three years in the four seasons. Intraspecific variation ranged from 0 to 2.46% whereas interspecific variation fluctuated from 3.07 to 14.59%, measuring 651 pb of the cytochrome oxidase subunit one (COI) gene. Neighbour-Joining analysis was carried out to investigate the molecular identification capabilities of the barcoding region, recovering almost all species as distinct monophyletic groups. The species groupings were generally consistent with morphological and molecular identifications. This work, which is the first with this intensive and extensive sampling in this area, shows that the COI barcode is an appropriate marker for unambiguous identification of forensically important Diptera in Spain.     

Detection of microRNAs in DNA Extractions for Forensic Biological Source Identification

Molecular‐based approaches for biological source identification are of great interest in the forensic community because of a lack of sensitivity and specificity in current methods. MicroRNAs (miRNAs) have been considered due to their robust nature and tissue specificity; however, analysis requires a separate RNA extraction, requiring an additional step in the forensic analysis workflow. The purpose of this study was to evaluate miRNA detection in blood, semen, and saliva using DNA extraction methods commonly utilized for forensic casework. RT‐qPCR analysis revealed that the tested miRNAs were consistently detectable across most tested DNA extraction methods, but detection was significantly reduced compared to RNA extracts in some biological fluids. DNase treatment was not necessary to achieve miRNA‐specific results. A previously developed miRNA panel for forensic body fluid identification was evaluated using DNA extracts, and largely demonstrated concordance with results from samples deriving from RNA extracts of semen, blood, and saliva.     

Validation of the 4‐aminophenol color test for the differentiation of marijuana‐type and hemp‐type cannabis

The analysis of cannabis plant material submitted to seized‐drug laboratories was significantly affected by the signing of the Agricultural Improvement Act of 2018, which defined hemp and removed it from the definition of marijuana in the Controlled Substances Act. As a result, field law enforcement personnel and forensic laboratories now are in need of implementing new protocols that can distinguish between marijuana‐type and hemp‐type cannabis. Colorimetric tests provide a cost‐effective and efficient manner to presumptively identify materials prior to submission to a laboratory for analysis. This work presents the validation of the 4‐aminophenol (4‐AP) color test and demonstrates its utility for discriminating between marijuana‐type and hemp‐type cannabis (i.e., typification). Validation studies included the testing of numerous cannabinoid reference materials, household herbs, previously characterized cannabis plant samples, and real‐case samples. The 4‐AP test reliably produces a pink result when the level of Δ⁹‐tetrahydrocannabinol (THC) is approximately three times lower than the level of cannabidiol (CBD). A blue result is generated when the level of THC is approximately three times higher than that of CBD. Inconclusive results are observed when the levels of THC and CBD are within a factor of three from each other, demonstrating the limitations of the test under those scenarios.     

The effect of congruence in policy priorities on electoral participation

This paper proposes that voters are more likely to turn out at elections if candidates and parties address their issue concerns in the election campaign. Voters with high levels of congruence in policy priorities should perceive the campaign as more interesting and the election as more relevant. In addition, the costs associated with the vote choice should be lower if voters' policy priorities are salient. The effect should be weakened by party identification, which acts both as a mobilising force and as a heuristic to the vote choice, making information costs less detrimental to turnout. The analysis, which links voter survey data with candidate survey and media content data from the 2009 German federal election, confirms the hypotheses.     

Party identification in the Czech Republic: inter-party hostility and party preference

This study introduces basic models of voting behavior and describes in greater detail the findings and starting points of the model of party identification. It recapitulates findings related to the voting behavior in the Czech Republic throughout the nineties, as well as the reasons leading to the application of the party identification model to the analyses of voting behavior. The influence of positive feelings toward the elected party and negative feelings toward the other parties are tested here. The study explores in particular the influence of inter-party hostility on the voting behavior, and tests it both separately and in combination with the subjective social class and subjective political orientation.     

Are children less reliable at making visual identifications than adults? A review

The current paper reviews research that has investigated developmental differences in lineup identification. A wealth of studies have shown that children can be as accurate as adults when making a correct identification from a target present lineup (TP), however children are more inclined to choose and thereby make a false identification from a target absent (TA) lineup, as compared to adults. The literature reviewed, suggests that the disparity between children's and adult's performances on TA lineups is due to children being unable to resist the social demands to choose someone from a lineup and/or the need to give a positive response. Employing a silhouette within a lineup, that can be chosen if the target is not recognised, appears to be the most successful technique for reducing false identifications made by child witnesses. Including a silhouette as a part of a lineup, along with the lineup administrator being attired in casual clothing, rather than a uniform, are two simple measures that could make child witness identification evidence more reliable.     

Distinguishing accurate from inaccurate eyewitness identifications with an optional deadline procedure

Abstract

Two experiments examined the efficacy of an optional deadline lineup procedure for distinguishing correct from incorrect eyewitness identification decisions. The procedure involved briefly presenting the lineup, removing the lineup from view, then giving participants the option of either making an identification decision or viewing the lineup again. When compared with participants operating under a forced deadline (i.e. forced to respond after the brief presentation) or standard lineup instructions, the optional deadline procedure identified participants with an impressive probability of having made a correct identification when used with target-present lineups and biased instructions. With unbiased instructions, the optional deadline produced clear discrimination between correct and incorrect identification decisions for choosers and, importantly, also for non-choosers. Possible strategies for improving the efficacy of the procedure are suggested.     

Mock jurors' perceptions of identifications made by intoxicated eyewitnesses

Abstract

Psychology research has generally neglected intoxicated eyewitnesses. The current study addressed this need by exploring mock jurors' perceptions of intoxicated witnesses. Undergraduate participants read summarized sexual or aggravated battery cases in which either the victim or a bystander identified the defendant under varying intoxication levels. They answered questions about the case and provided verdicts. Participants were sensitive to the effect that intoxication may have on witnesses' cognitive ability, but not to varying degrees of intoxication. Neither the role of the eyewitness nor the type of crime committed had an effect on perceptions of witness impairment. Participants' perceptions of witness impairment informed identification credibility ratings, and credibility assessments affected verdicts. Impairment and credibility ratings fully mediated intoxication's effect on verdicts. Unlike much prior research, our results suggest that mock jurors can consider potentially important witness information when rendering verdicts.     

刑事人身辨认证据种类辨析及相关证据规则的适用

2012年3月14日,全国人大通过了经过全面修改的《刑事诉讼法》,在新《刑事诉讼法》中,辨认笔录第一次以法定证据的形式出现在了我国的刑事立法中.随后出台的配套司法解释以《刑事诉讼法》为依据,构建了较为完备的人身辨认证据规则体系,这改变了长期以来辨认笔录作为证据于法无据、作为侦查线索运用混乱的失范局面,是一个显著的进步.但规范层面的概念界定并没有完全消除理论上对于人身辨认证据种类方面的争论,人身辨认在证明对象、心理机制和证明方式上与相关言词证据千丝万缕的联系为人身辨认证据规则的适用增加了困难.因此,有必要从人身辨认证据种类界定入手,探究辨认证据在证据规则适用上的特殊问题,力图强化辨认证据的审查判断,以降低错误辨认的可能性及其对案件实体结果的不利影响.