The use of error rates to predict and characterize the efficacy of presumptive field tests

From a forensic perspective, a presumptive test, one which indicates the presence or absence of a certain target material such as blood, is an invaluable tool. Among these tests, there are different specificities, sensitivities, and shelf lives. The accuracy of a test is an algebraic combination of the specificity and sensitivity of the test. Each test has limitations as given by its false positive and false negative rates. The aim of this study was to illustrate how the false positive and false negative rates are to be properly determined using a simulation study for the phenolphthalein test. New presumptive tests must be properly evaluated/validated through testing of commonly encountered household items and other potentially probative items usually found at crime scenes, however, the makeup of test sets must appropriately capture all error rates. In order to correctly use these results when the test is applied to an unknown sample recovered at a crime scene, the error rates cannot be applied directly to estimate whether or not the sample is actually the analyte of interest. In a validation study, the forensic scientist calculates the false positive rate as the p(Positive Reaction|Blood), whereas at the scene, the crime scene investigator wishes to determine the p(Blood|Positive Reaction). All crime scene investigators need to ensure that the conditional is not transposed when interpreting such results. Furthermore, this work provides a model for the assessment of a multiple test diagnostic system intended for investigators.     

Radiodense bullet wipe around osseous entrance gunshot wounds

“Bullet wipe” is the material deposited by a bullet on any surface with which it comes into contact after it is fired and may contain debris from the gun barrel, including particles of primer and metal fragments from previously fired bullets. X‐ray analysis is a non‐destructive method by which traces of metallic elements can be visually detected. The analysis of osseous defects for radiodense bullet wipe (RBW) assists in determining the presence or absence of perforating gunshot wounds, especially in fragmented, skeletonized remains. The aim of our current study was to determine the frequency of RBW around entrance firearms injuries that perforated bone. We prospectively analyzed entrance gunshot wounds for RBW over a three‐year period using digital X‐ray analysis (n = 59). We retrospectively reviewed the corresponding autopsy reports to determine the frequency of RBW by biologic sex, reported ancestry, age‐at‐death, location of wound, manner of death, range of fire, bullet caliber, and presence of bullet jacket. Data were analyzed by Fisher's exact test or Chi‐square test with significance levels accepted at p < 0.05. RBW was present in 66% (n = 39) of examined cases. Decedent characteristics did not significantly alter RBW distribution, including biologic sex (p = 0.75), reported ancestry (p = 0.49), and age‐at‐death (p = 0.43). Additionally, the location of the osseous entrance gunshot wound, manner of death, range of fire, and cartridge caliber did not affect RBW detection. All cases involving non‐jacketed rounds (n = 5) showed RBW (p = 0.30). To our knowledge, this study is the first to report the frequency of RBW detection from osseous entrance gunshot wounds.     

The Lure of New Jobs: How Framing Impacts Perceptions of Local Subsidies for Sports Teams

Municipalities often use public funds to support private projects in pursuit of economic growth or improved quality of life. How does the framing of municipal subsidies impact public support for such funding? We examine the case of government-funded minor league baseball stadiums to address this question. Using nationally representative survey data, we find respondents are much more likely to support funding for stadiums when told that baseball will bring jobs and improve the local economy, compared to other frames. Local governments may therefore rely on positive, economic frames to gain public support, despite a lack of evidence that sports stadiums deliver net economic benefits.     

Does recent physical and sexual victimization affect further substance use for adult drug-involved offenders?

This study examined whether physical and sexual victimization experiences were related to further substance use for a sample of drug-involved adult offenders and whether this increase could be attributed to depression experienced after the victimization occurred. A total of 674 men and 284 women from the longitudinal Multisite Adult Drug Court Evaluation (MADCE) were included in analyses. The study included 23 drug court and 6 comparison sites. Study participants completed three interviews: at baseline enrollment and then at 6 and 18 months after baseline. Multilevel path modeling showed that physical and sexual victimization experiences during the year before the baseline interview were associated with further substance use at 18 months and that this relationship was mediated by depression. All relationships held for both men and women, and beyond the contribution of several control variables, including drug court program participation. Public health and criminal justice personnel working with substance-using offenders should screen individuals for victimization-related trauma and, if identified, provide assistance to evaluate and improve such individuals' mental health and, subsequently, decrease their likelihood of using substances.     

Validation of tool mark analysis of cut costal cartilage

This study was designed to establish the potential error rate associated with the generally accepted method of tool mark analysis of cut marks in costal cartilage. Three knives with different blade types were used to make experimental cut marks in costal cartilage of pigs. Each cut surface was cast, and each cast was examined by three analysts working independently. The presence of striations, regularity of striations, and presence of a primary and secondary striation pattern were recorded for each cast. The distance between each striation was measured. The results showed that striations were not consistently impressed on the cut surface by the blade's cutting edge. Also, blade type classification by the presence or absence of striations led to a 65% misclassification rate. Use of the classification tree and cross-validation methods and inclusion of the mean interstriation distance decreased the error rate to c. 50%.     

Knowing when the camera lies: Judicial instructions mitigate the camera perspective bias

Purpose. Videotaped confession evidence elicits harsher evaluations against a defendant if initially recorded with the camera focused primarily on the suspect, compared with other presentation formats. Unfortunately, most videotaped confession evidence employs this biasing suspect‐focus camera perspective format, leaving defendants with no recourse. The present study examined the utility of judicial instructions in mitigating the effects of the camera perspective bias on individual juror verdicts. Methods. Through random assignment, 156 mock jurors did or did not receive explicit instructions to correct for the camera perspective bias prior to viewing a video recording of an authentic true or false confession. Results. As expected, mock jurors who received instructions to correct for the camera perspective bias reported more lenient judgments of confessor guilt after viewing a suspect‐focus confession recording compared to those who did not receive such instructions. However, this relative leniency emerged only in response to false, and not true, confessions. Conclusions. Results demonstrated that judicial instructions used in the present research mitigated the effect of camera perspective on mock‐juror judgments of suspect guilt.     

Blind lineup administration as a prophylactic against the postidentification feedback effect

Confidence and other testimony-relevant judgments may be distorted when witnesses are given confirming postidentification feedback, and double-blind procedures-wherein the lineup administrator does not know the identity of the suspect-are a commonly proposed, but untested, remedy for this effect. In the current study, mock witnesses viewed a staged crime video followed by a target-present or target-absent lineup where the administrator was or was not presumed to know the identity of the suspect. After making an identification decision, witnesses were or were not given realistic, but nonidentification-specific, feedback, and then confidence and other judgments were assessed. A significant interaction was found between blind condition and feedback such that feedback inflated confidence and other judgments in presumed nonblind conditions only; feedback had no effect on participants in presumed blind conditions. As predicted by the selective cue integration framework-a theoretical model suggested to explain the interaction between presumed blind administration and feedback-this interaction was significant only for inaccurate participants. These results suggest that blind administration may serve as a prophylactic against the negative effects of postidentification feedback. In addition, the effectiveness of our subtle feedback in influencing judgments suggests that lineup administrators should take care not to provide any feedback to eyewitnesses. (PsycINFO Database Record (c) 2012 APA, all rights reserved).     

Supervision practices in specialty mental health probation: What happens in officer-probationer meetings?

As the correctional population continues to increase, probation agencies struggle to adequately supervise offenders with unique needs, including those with mental disorder. Although more than 100 U.S. probation agencies have implemented specialty mental health case-loads, little is known about their practices. Based on detailed observations of 83 audio-taped meetings, we examined interactions between probationers and officers in a prototypic specialty agency, focusing on the extent to which practices comport with evidence-based risk reduction principles. We found that specialty officers (a) more frequently discussed probationers' general mental health than any individual criminogenic need, (b) chiefly questioned, directed, affirmed, and supported (rather than confronted) probationers, and (c) relied more heavily on neutral strategies and positive pressures (e.g., inducements) rather than negative pressures (e.g., threats of incarceration) to monitor and enforce compliance. Implications for "what works" to promote community integration for probationers with mental disorder are discussed.