Our multisite randomized controlled trial reported that police body-worn cameras (BWCs) had, on average, no effect on recorded incidents of police use of force. In some sites, rates of use of force decreased and in others increased. We wanted to understand these counter-intuitive findings and report pre-specified subgroup analyses related to officers’ discretion on activating the BWCs.
Methods
Using pre-established criteria for experimental protocol breakdown in terms of treatment integrity, ten experimental sites were subgrouped into “high-compliance” (no officer discretion applied to when and where BWCs should be used; n?=?3), “no-compliance” (treatment integrity failure in both treatment and control conditions; n?=?4), and tests where officers applied discretion during treatment group but followed protocol in control conditions only (n?=?4).
Results
When officers complied with the experimental protocol and did not use discretion, use of force rates were 37 % lower [SMD?=?(?.346); SE?= .137; 95?% CI (?.614) – (?.077)]; when officers did not comply with treatment protocol (i.e., officers chose when to turn cameras on/off), use of force rates were 71 % higher [SMD?= .392; SE?= .130; 95?% CI (.136) – (.647)], compared to control conditions. When full discretion (i.e., overall breakdown of protocol) was applied to both treatment and control conditions, null effects were registered [SMD?= .009; SE=.070; 95?% CI (?.127) – (.146)], compared to control conditions.
Conclusions
BWCs can reduce police use of force when then officers’ discretion to turn cameras on or off is minimized—in terms of both case types as well as individual incidents. BWCs ought to be switched on and the recording announced to suspects at early stages of police–public interactions. Future BWCs tests should pay close attention to adherence to experimental protocols.
George Ritzer, The McDonaldisation Thesis (Sage, London, 1998), 212 pp., ISBN 0–7619–5540–2 (pb)
Terrell Carver and Veronique Mottier (eds), Politics of Sexuality. Identity, gender, citizenship (Routledge, London, 1998), 200 pp., ISBN 0–415–16953–4 (hb)
Hein Marais, South Africa: Limits to Change. The Political Economy of Transformation (Zed Books, London, 1998), 290 pp., ISBN 1–85649–544–2 (pb)
Taras Kuzio, Ukraine: State and Nation Building (Routledge, London, 1998), 298 pp., ISBN 0–415–17195–4 (hb)
Alan M. Dershowitz, Sexual McCarthyism: Clinton, Starr, and the Emerging Constitutional Crisis (Basic Books, New York, 1998), 275 pp., ISBN 0–465–01628–6 (hb)
Timothy Hoye, Japanese Politics: Fixed and Floating Worlds (Prentice Hall, New Jersey, 1999), 233 pp., ISBN 0–13–271289‐X (pb)
Julia Sudbury, Other Kinds of Dreams: Black Women's Organisations and the Politics of Transformation (Routledge, London, 1998), 282 pp., ISBN 0–415–16732–9 (pb) 相似文献
The effect of the shape of semiconductor nanocrystals on their performance for visualising latent fingermarks was investigated for the first time. Highly luminescent CdSe/CdS core/shell nanocrystals in rod and spherical shapes were synthesised in organic solvent and transferred to aqueous solution using ligand exchange. The 3-mercaptopropionic acid coated nanorods and nanospheres were characterised using electron microscopy and UV-visible absorbance and luminescence spectrophotometry. A simple and rapid development of fresh to less than a week-old natural fingermarks from 4 donors (male and female) on non-porous surfaces including glass slides, aluminium foil and germanium disks using both CdSe/CdS core/shell nanorods and spherical dots was achieved, wherein nanorods demonstrated an enhanced development of ridge details in comparison to the spherical dots. 相似文献
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Abstract: Plant material is frequently encountered in criminal investigations but often overlooked as potential evidence. We designed a DNA‐based molecular identification system for 100 Australian grasses that consisted of a series of polymerase chain reaction assays that enabled the progressive identification of grasses to different taxonomic levels. The identification system was based on DNA sequence variation at four chloroplast and two mitochondrial loci. Seventeen informative indels and 68 single‐nucleotide polymorphisms were utilized as molecular markers for subfamily to species‐level identification. To identify an unknown sample to subfamily level required a minimum of four markers or nine markers for species identification. The accuracy of the system was confirmed by blind tests. We have demonstrated “proof of concept” of a molecular identification system for trace botanical samples. Our evaluation suggests that the adoption of a system that combines this approach with DNA sequencing could assist the morphological identification of grasses found as forensic evidence. 相似文献
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Venous air embolism occurs when air enters the venous system. The main causes of venous air embolism include medical procedures, neck and head trauma, and injuries of the genitals. Self‐induced suicidal (and intentional) air embolism is extremely rare. The authors report a rare case of a suicidal air embolism committed using a self‐made tool composed of a plastic bottle and an infusion set, injecting nearly 2000 mL of air into the cubital vein. The toxicological analysis suggested that midazolam, together with air, was also injected into the circulation using the same bottle and infusion set. 相似文献