Conducted Energy Weapon Research Articles

A Comparison of Police Use of Force by Male and Female Officers in Canada: Rates, Modalities, Effectiveness, and Injuries

Research has reported inconsistent findings with respect to how female and male police officers use force. This study examined this issue in a Canadian context. Use of force data over 9 years were collected from a large Canadian police agency. The results demonstrated that, overall, female officers used force less frequently than male officers relative to the number of female and male officers within the participating police agency. Female officers had lower odds of using physical control “hard” options (e.g., stuns and strikes) and higher odds of using intermediate weapons (e.g., conducted energy weapon) compared with male officers. Female officers also generally reported less effectiveness, more injuries to themselves, and fewer injuries to subjects related to their use of force compared with male officers. Literature on police use of force and social role theory are used to help explain the findings, and recommendations for improving outcomes in police–public interactions are suggested.

Manifestation of TASER drive stun burn marks on fabrics.

The TASER® is a type of conducted energy weapon (CEW) used with increasing frequency by law enforcement to subdue subjects in circumstances where compliance is necessary. When operated in the drive stun method of deployment, the electrodes at the head of this CEW are intended to make direct contact with a surface, generating heat and light which may result in burn marks as a by-product of the electrical discharge that occurs. This research aims to tackle a crucial gap in CEW research that fails to address the appearance of burn marks on fabrics. A drive stun duration (DSD) of 1, 3, and 5s was used with three TASER models (X26P, X2, & TASER 7) on three fabrics (white 100% cotton, 100% polyester, 35:65 cotton-polyester blend) with an underlying backing of pork hock. Using a Keyence VHX-6000 confocal microscope, high magnification images were taken to observe any qualitative changes to the fabric. On polyester fabric, with increasing DSD, darker brown discoloration occurred. Additionally, on polyester fabric, the spatial orientation of the burn marks corresponded with that of the electrodes at the muzzle of each TASER model. These features enabled the correct identification of the TASER model and DSD on polyester fabric in the blind tests performed. Evidence of burn marks on cotton and blend fabrics were both limited and inconsistent such that no features were sufficiently unique to link them to any TASER model or DSD. Despite this, overall features such as discoloration and the formation of holes on these fabric types may be sufficiently unique to suggest the use of a CEW.

Situational and Ecological Predictors of Conducted Energy Weapon Application Severity

Despite being touted as a “less lethal” use-of-force option, conducted energy weapons (CEWs) do pose some risk of injury to civilians, and thus warrant empirical examination. CEWs provide users with multiple use modes constituting various levels of severity; yet apart from the work of Somers and colleagues, almost no research exists investigating these levels of severity. Further, research findings on the impact of suspect resistance on CEW deployment are somewhat mixed. We contribute an innovative application of environmental criminology in a Canadian setting by exploring situational and ecological predictors of CEW application severity, with special attention being paid to reasons cited for CEW use and the impact of subject resistance level. Using all 393 Ontario Provincial Police CEW-related use-of-force reports over a two-year period, we find probe deployment to be the most common level of CEW application severity, irrespective of subject resistance level, and even when officers and subjects are in close proximity to one another. Application of CEW for the purpose of effecting an arrest is consistently the strongest predictor of CEW application severity without any mediating effect of subject resistance level or presence of a weapon. The impact of applying CEWs for the purpose of effecting arrests on CEW application severity is partially mediated by lighting visibility. Results are discussed.

Predicting firearm and CEW displays as police officers' response to resistance

PurposeThe purpose of the study was to identify factors associated with officer firearm and conducted energy weapon displays. Our specific concern was whether black subjects were more likely to have firearms drawn against them relative to other subjects. MethodsOfficer- and incident-level “response to resistance” data from the New Orleans Police Department were analyzed. Logistic regression models controlling for officer, subject, and situational factors were estimated to predict officer weapon draws. ResultsWhen analyzing all officer-level actions, black subjects were more likely to have firearms drawn against them than other subjects, but subject race was insignificant in incident-level analyses. Additionally, situational characteristics explained more variance in the data than officer or subject characteristics alone. ConclusionsWe found no consistent evidence of racial bias in firearm draws. Results hinged to an extent on the samples analyzed and statistical models estimated. In addition, our findings apply solely to one city and highlight the complexity of use-of-force research and the need for further replication.

Emergency Department Evaluation After Conducted Energy Weapon Use: Review of the Literature for the Clinician.

Conductive energy weapons (CEWs) are used daily by law enforcement, and patients are often brought to emergency departments (EDs) for medical clearance. Our aim was to review the medical literature on the topic of CEWs and to offer evidence-based recommendations to emergency physicians for evaluation and treatment of patients who have received a CEW exposure. A MEDLINE literature search from 1988 to 2018 was performed and limited to human studies published from January 1, 1988 to November 1, 2018 written in English with the following keywords: TASER, conductive energy device(s), electronic weapon(s), conductive energy weapon(s), non-lethal weapon(s), conducted energy device(s), conducted energy weapon(s), conductive electronic device(s), and electronic control device(s). Studies identified then underwent a structured review from which results could be evaluated. Two hundred and sixty-three articles on CEWs were screened and 37 appropriate articles were rigorously reviewed. Evaluation and treatment recommendations are presented. These studies did not report any evidence of dangerous laboratory abnormalities, physiologic changes, or immediate or delayed cardiac ischemia or dysrhythmias after exposure to CEW electrical discharges of up to 15s. The current medical literature does not support routine performance of laboratory studies, electrocardiography, or prolonged ED observation or hospitalization for ongoing cardiac monitoring after CEW exposure in an otherwise asymptomatic awake and alert patient.

TASER® Exposure and Cognitive Impairment

Research SummaryThis study reports findings from a randomized controlled trial that examined the effects of the TASER® (a conducted energy weapon sold by TASER International, Scottsdale, Arizona) on several dimensions of cognitive functioning. The research demonstrated that in a sample of healthy human volunteer participants, TASER exposure led to significant and substantial reductions in (a) short‐term auditory recall and (b) abilities to assimilate new information through auditory processes. The effects lasted up to 1 hour for most subjects, almost all of whom returned to baseline 60 minutes postexposure.Policy ImplicationsThe study applies the findings of reduced cognitive functioning among healthy participants in a laboratory setting to criminal suspects in field settings and questions the abilities of “average” suspects to waive their Miranda rights knowingly, intelligently, and voluntarily within 60 minutes of a TASER exposure. The study poses the question: What would it cost police to wait 60 minutes after a TASER deployment before engaging suspects in custodial interrogations?

40‐Hz Square‐Wave Stimulation Requires Less Energy to Produce Muscle Contraction: Compared with the TASER®X26 Conducted Energy Weapon

Conducted energy weapons (CEWs) (including the Advanced TASER(®) X26 model produced by TASER International, Inc.) incapacitate individuals by causing muscle contractions. In this study using anesthetized swine, the potential incapacitating effect of primarily monophasic, 19-Hz voltage imposed by the commercial CEW was compared with the effect of voltages imposed by a laboratory device that created 40-Hz square waves. Forces of muscle contraction were measured with the use of strain gauges. Stimulation with 40-Hz square waves required less pulse energy than stimulation with the commercial CEW to produce similar muscle contraction. The square-pulse stimulation, at the higher repetition rate, caused a more complete tetanus at a lower energy. Use of such a simple shape of waveform may be used to make future nonlethal weapon devices more efficient.

A Quantum of Force: The Consequences of Counting Routine Conducted Energy Weapon Punctures as Injuries

In a recent paper, researchers reported increases in the risk of citizen injury associated with police use of conducted energy devices (CEWs), a finding that is contrary to that reported in most previous studies. These authors speculate that the differences in findings when compared to other similar studies may be due, in part, to the exclusion of routine CEW dart punctures as injuries by other researchers, and they called on the research community to collectively agree on how CEW injuries should be operationalized. In this paper, we empirically demonstrate the differences in findings when routine CEW puncture wounds are included as citizen injuries and when they are not. Ultimately, we reject the authors’ measurement approach as inconsistent with how injuries associated with other types of force are routinely coded and measured.

Effects of a TASER® conducted energy weapon on the circulating red-blood-cell population and other factors in Sus scrofa

In previous studies hematocrit has been consistently increased in an anesthetized animal model after exposures to TASER(®) conducted energy weapons (CEWs). In the present study we analyzed changes in blood cell counts and red blood cell membrane proteins following two 30-s applications of a TASER C2 device (which is designed for civilian use). Hematocrit increased significantly from 33.2 ± 2.4 (mean ± SD) to 42.8 ± 4.6 % immediately after CEW exposure of eleven pigs (Sus scrofa). Red blood cell count increased significantly from 6.10 ± 0.55 × 10(12)/L to 7.45 ± 0.94 × 10(12)/L, and mean corpuscular volume increased significantly from 54.5 ± 2.4 fl to 57.8 ± 2.6 fl. Mean corpuscular hemoglobin concentration decreased significantly from 20.5 ± 0.7 to 18.5 ± 0.6 mM. Thirty protein spots (from two-dimensional sodium dodecyl sulfate polyacrylamide gel electrophoresis, selected for detailed comparison) exhibited greater densities 30-min post-exposure compared with pre-exposure values. A greater number of echinocytes were observed following CEW exposure. On the basis of these results it appears that, during the strong muscle contractions produced by TASER CEWs, a specific population of red blood cells (RBCs) may be released from the spleen or other reservoirs within the body. The total time of CEW exposure in the present study was relatively long compared with exposures in common law-enforcement scenarios. Despite statistically significant changes in red blood cell counts (and other measures directly related to RBCs), the alterations were short-lived. The transient nature of the changes would be likely to counteract any potentially detrimental effects.

Emergency Department Evaluation after Conducted Energy Weapon Use: Review of the Literature for the Clinician

Conductive energy weapons (CEWs) are used daily by law enforcement, and patients are often brought to an emergency department (ED) for medical clearance. To review the medical literature on the topic of CEWs and to offer evidence-based recommendations to Emergency Physicians for evaluation and treatment of patients who have received a CEW exposure. A MEDLINE literature search from 1988 to 2010 was performed and limited to human studies published from January 1988 to January 20, 2010 for English language articles with the following keywords: TASER, conductive energy device(s), electronic weapon(s), conductive energy weapon(s), non-lethal weapon(s), conducted energy device(s), conducted energy weapon(s), conductive electronic device(s), and electronic control device(s). Studies identified then underwent a structured review from which results could be evaluated. There were 140 articles on CEWs screened, and 20 appropriate articles were rigorously reviewed and recommendations given. These studies did not report any evidence of dangerous laboratory abnormalities, physiologic changes, or immediate or delayed cardiac ischemia or dysrhythmias after exposure to CEW electrical discharges of up to 15 s. The current medical literature does not support routine performance of laboratory studies, electrocardiograms, or prolonged ED observation or hospitalization for ongoing cardiac monitoring after CEW exposure in an otherwise asymptomatic awake and alert patient.

Cardiac safety of conducted electrical devices in pigs and their effect on pacemaker function

Objective The aims of this study are to evaluate the cardiac safety of the Stinger S-200 Conducted Energy Weapon Device (CED) (Stinger Systems, Tampa, Fla) on a human-sized pig model and to test the effect of various commercially available CEDs, specifically the Stinger S-200, TASER M26 (Taser International, Scottsdale, Ariz), and TASER X26 on pacemaker function. Methods Two groups of pigs, divided based on weight as group 1 (n = 3, 67.3 ± 4.7 kg) and group 2 (n = 3, 89.3 ± 1.2 kg), were used. In protocol 1, the Stinger S-200 was applied in multiple different orientations to simulate possible field scenarios across the heart. In protocol 2, a single-chamber bipolar lead connected to a pacemaker was placed in the right ventricle of the pig, and different CEDs were applied to test the pacemaker function during CED application. Results In protocol 1, the S-200 was applied a total of 216 times in the 6 pigs, and neither episodes of ventricular fibrillation nor episodes of sustained ventricular tachycardia were noted. In protocol 2, the CED discharges (1) were recognized by the pulse generator and sensed as either high-rate atrial or ventricular activity, (2) did not affect the native rhythm, (3) did not conduct down the lead systems to cause any extra systoles, and (4) had no effect on paced rhythm. Conclusions In this model, the application of the S-200 in various orientations across the heart did not result in any sustained abnormal cardiac rhythms. None of the tested CEDs adversely affected the functioning of the tested pacemaker. Stinger Systems has now replaced the S-200 with the S-200T with a different output.

Pulse Variations of a Conducted Energy Weapon (Similar to the TASER® X26 Device): Effects on Muscle Contraction and Threshold for Ventricular Fibrillation*

Conducted energy weapons (such as the Advanced TASER X26 model produced by TASER International), incapacitate individuals by causing muscle contractions. To provide information relevant to development of future potential devices, a "Modifiable Electronic Stimulator" was used to evaluate the effects of changing various parameters of the stimulating pulse. Muscle contraction was affected by pulse power, net/gross charge, pulse duration, and pulse repetition frequency. The contraction force increased linearly as each of these factors was increased. Elimination of a precursor pulse from X26-like pulses did not have a significant effect on the normalized force measured. Muscle-contraction force increased as the spacing increased from 5 to 20 cm, with no further change in force above 20 cm of spacing. Therefore, it is suggested that any future developments of new conducted energy weapons should include placement of electrodes a minimum of 20 cm apart so that efficiency of the system is not degraded. In the current study, the 50% probability of fibrillation level of X26-like pulses ranged from 4 to 5 times higher than the X26 itself. Relatively large variations about the X26 operating level were found not to result in fibrillation or asystole. Therefore, it should be possible to design and build an X26-type device that operates efficiently at levels higher than the X26.

Physiological effects of the TASER® C2 conducted energy weapon

Physiological effects of the TASER® C2 conducted energy weapon

Physiological effects of the TASER® C2 conducted energy weapon

In previous studies, exposure to conducted energy weapons (CEWs) (such as TASER International's Advanced TASER X26 device) resulted in leg muscle contraction, acidosis, increased blood electrolytes, and other biochemical and physiological changes. In the current study, experiments were performed to examine the effects of exposures to TASER International's "C2" CEW, which is specifically marketed to civilian rather than law-enforcement users. Ten pigs (Sus scrofa) were sedated with an intramuscular injection of Telezol (tiletamine HCl and zolazepam HCl) and intubated. General anesthesia was maintained with an IV propofol infusion. Applications of the C2 device for 30 s resulted in extensive muscle contraction and significant increases in heart rate and hematocrit, and in blood levels of pCO2, lactate, glucose, and potassium, sodium, and calcium ions. Significant decreases were observed in blood oxygen saturation, pO2, and pH. Qualitatively, many of these changes were consistent with previous reports in the literature dealing with studies of muscle stimulation or exercise. The changes in blood pCO2, pO2, electrolytes, lactate, and pH, however, were greater than in a previous study of three repeated 5-s exposures to the X26 CEW commonly used by law-enforcement personnel. On the basis of the results, potential detrimental effects due to use of the "citizen-version" TASER C2 CEW may be more likely than limited intermittent applications of the X26 CEW.

Thoracic Compression Fractures as a Result of Shock From a Conducted Energy Weapon: A Case Report

The Taser is an electrical conducted energy weapon used by law enforcement officers throughout the United States and the world. Though generally regarded as safe, conducted energy weapons can produce injuries. In this case report we describe for the first time thoracic spine compression fractures resulting from a conducted energy weapon discharge. Physicians who may care for patients who have been exposed to a conducted energy weapon discharge should be aware of this as a possible complication.

340: Cardiac Effects of the Taser Conducted Energy Weapon

340: Cardiac Effects of the Taser Conducted Energy Weapon