The role of death qualification in venirepersons' evaluations of aggravating and mitigating circumstances in capital trials

Death qualification is a part of voir dire that is unique to capital trials. Unlike all other litigation, capital jurors must affirm their willingness to impose both legal standards (either life in prison or the death penalty). Jurors who assert they are able to do so are deemed “death-qualified” and are eligible for capital jury service: jurors who assert that they are unable to do so are deemed “excludable” or “scrupled” and are barred from hearing a death penalty case. During the penalty phase in capital trials, death-qualified jurors weigh the aggravators (i.e., arguments for death) against the mitigators (i.e., arguments for life) in order to determine the sentence. If the aggravating circumstances outweigh the mitigating circumstances, then the jury is to recommend death; if the mitigating circumstances outweigh the aggravating circumstances, then the jury is to recommend life. The jury is free to weigh each aggravating and mitigating circumstance in any matter they see fit. Previous research has found that death qualification impacts jurors' receptiveness to aggravating and mitigating circumstances (e.g., Luginbuhl & Middendorf, 1988). However, these studies utilized the now-defunct Witherspoon rule and did not include a case scenario for participants to reference. The purpose of this study was to investigate whether death qualification affects jurors' endorsements of aggravating and mitigating circumstances when Witt, rather than Witherspoon, is the legal standard for death qualification. Four hundred and fifty venirepersons from the 11 th Judicial Circuit in Miami, Florida completed a booklet of stimulus materials that contained the following: two death qualification questions; a case scenario that included a summary of the guilt and penalty phases of a capital case; a 26-item measure that required participants to endorse aggravators, nonstatutory mitigators, and statutory mitigators on a 6-point Likert scale; and standard demographic questions. Results indicated that death-qualified venirepersons, when compared to excludables, were more likely to endorse aggravating circumstances. Excludable participants, when compared to death-qualified venirepersons, were more likely to endorse nonstatutory mitigators. There was no significant difference between death-qualified and excludable venirepersons with respect to their endorsement of 6 out of 7 statutory mitigators. It would appear that the Furman v. Georgia (1972) decision to declare the death penalty unconstitutional is frustrated by the Lockhart v. McCree (1986) affirmation of death qualification. ^

Improving the scientific reliability of biological detection of explosives by Canis familiaris: Active odour signatures and their implications

The use of canines as a method of detection of explosives is well established worldwide and those applying this technology range from police forces and law enforcement to humanitarian agencies in the developing world. Despite the recent surge in publication of novel instrumental sensors for explosives detection, canines are still regarded by many to be the most effective real-time field method of explosives detection. However, unlike instrumental methods, currently it is difficult to determine detection levels, perform calibration of the canines' ability or produce scientifically valid quality control checks. Accordingly, amongst increasingly strict requirements regarding forensic evidence admission such as Frye and Daubert, there is a need for better scientific understanding of the process of canine detection. ^ When translated to the field of canine detection, just like any instrumental technique, peer reviewed publication of the reliability, success and error rates, is required for admissibility. Commonly training is focussed towards high explosives such as TNT and Composition 4, and the low explosives such as Black and Smokeless Powders are added often only for completeness. ^ Headspace analyses of explosive samples, performed by Solid Phase Microextraction (SPME) paired with Gas Chromatography - Mass Spectrometry (GC-MS), and Gas Chromatography - Electron Capture Detection (GC-ECD) was conducted, highlighting common odour chemicals. The odour chemicals detected were then presented to previously trained and certified explosives detection canines, and the activity/inactivity of the odour determined through field trials and experiments. ^ It was demonstrated that TNT and cast explosives share a common odour signature, and the same may be said for plasticized explosives such as Composition C-4 and Deta Sheet. Conversely, smokeless powders were demonstrated not to share common odours. An evaluation of the effectiveness of commercially available pseudo aids reported limited success. The implications of the explosive odour studies upon canine training then led to the development of novel inert training aids based upon the active odours determined. ^

Quantification of standards of proof thresholds in criminal and civil litigation

Standards of proof in law serve the purpose of instructing juries as to the expected levels of confidence in determinations of fact. In criminal trials, to reach a guilty verdict a jury must be satisfied beyond a reasonable doubt, and in civil trials by a preponderance of the evidence. The purposes of this study are to determine the quantitative thresholds used to make these determinations; to ascertain the levels of juror agreement with basic principles of justice; and to try to predict thresholds and beliefs by juror personality characteristics. Participants read brief case descriptions and indicated thresholds in percentages, their beliefs in various principles, and completed three personality measures. A 92-94% threshold in criminal and an 80% threshold in civil matters was found; but prediction by personality was not supported. Significant percentages of jurors disavowed the presumptions of innocence and right to counsel.