Evaluating cardiac risks of TASER: An in-depth case study through probable current analysis.

This study investigates the cardiac safety concerns related to TASER discharges centering on a pivotal case that marked the first TASER-related fatality in South Korea. Employing Pratt et al.'s theoretical framework, the research evaluates the potential for ventricular fibrillation (VF) from these discharges. The methodology incorporated a high-resolution waveform analysis using sophisticated equipment and considered specific incident details, including dart impact locations verified through a forensic examination. A human body impedance of 500 Ω, chosen based on empirical studies and coupled with non-inductive resistance for high-voltage handling, was utilized in the model. By applying a heart-current factor from IEC 60479 standards, the study found a VF risk of up to 5% depending on the impact location and current pathways. In this specific case, although the calculated risk did not exceed critical thresholds, the VF risk was high enough to suggest that TASER discharges played a role in the fatal outcome. This study underscores the importance of dart impact location in TASER safety evaluations, contributing to a broader understanding of TASER cardiac risks and providing a basis to advocate for rigorous safety protocols.

Conducted Electrical Weapon Fire Risk in the Presence of Supplemental Oxygen.

BACKGROUND: Conducted electrical weapons (CEWs) are nonlethal weapons used in tactical environments. Tactical EMS (TEMS) operators provide patient care in environments where CEWs are present. CEWs may produce a spark that can be a source of ignition. When supplemental oxygen is in use by a TEMS operator, the flammability risk from the CEW is unknown. METHODS: We measured oxygen levels over 20 minutes in an enclosed space with a supplemental oxygen source maximally flowing. Measurements were taken at various distances from the oxygen source to establish baseline concentrations. These concentrations were replicated within a plexiglass box where a CEW was activated to create a sparking arc between probes embedded in a fresh swine shoulder (with skin intact). Various flammable materials, typically found in a patient care setting were used as potential fuel sources. RESULTS: The highest oxygen levels were achieved directly at the source. At 15cm from the source, the maximum oxygen concentration was 31.5%. Within the box, ignition was only achieved at oxygen concentrations greater than 45% and only when human hair was present as fuel. No ignition was achieved at oxygen levels below this regardless of the tested fuel present. CONCLUSION: Ignition from a CEW is possible at supplemental oxygen levels greater than 45% when human hair is present. In an enclosed space, oxygen concentration levels of 45% are only present within 15cm of a flush rate oxygen source. The likelihood of CEW-caused ignition in such settings with supplemental oxygen in use is extremely low.

Taser-Related Ocular Injuries: A Review of the Literature and Medico-Legal Implications.

PURPOSE: Electric weapons have dangers associated with their use, such as burns and trauma related with the impacts of uncontrolled falls, even though they often minimize morbidity and mortality. The exact visual outcome of the damage inflicted is unknown, even though numerous studies have been documented in the literature about the ocular damage induced by the use of these tools. METHODS: We present a narrative review of types of eye damage associated with the use of the Taser. The following search terms were used to identify eligible articles through the PubMed database: "TASER", "Conducted Electric Weapons", "CEWs". RESULTS: A total of 15 articles were included with information about 38 patients with eye damage associated with the use of taser. The majority of patients were males. In most cases the mechanism of injury was the penetration of the probe inside the eye. Clinical manifestations of ocular damage were present in only 18 out of 38 cases and varied according to the type of damage mechanism. Indeed, the cases in which the probe had penetrated the eye showed more severe clinical manifestations with a poor visual outcome. CONCLUSION: In conclusion, the introduction of taser use for law enforcement requires serious consideration and adequate training for officers.

Damage characteristics of fabrics created by TASER probes.

TASER® weapons are conducted energy weapons (CEWs) that are frequently used by police departments around the world. CEWs can be deployed in two methods: drive stun application and probe deployment. This study aims to examine damages caused by TASER devices on fabrics and whether types of fabric material and TASER models could contribute to different damage features. Three types of white fabric were used, including 100% cotton, 100% polyester, and 65:35 polyester-cotton blend. Three models: TASER X26P, TASER X2, and TASER 7 were shot onto each type of fabric, with five repetitions each. Each damaged area on the fabric caused by a probe is a sample (n = 90) and was examined with a Keyence digital microscope. Images were captured by the Keyence microscope and measurements were recorded, including damage dimensions, fabric condition, evidence of burning, and extra findings. The presence of fused yarn ends was found to be statistically significant across the fabric types, and no damage features were found that may assist in the identification of TASER models. Other damage features including damage dimensions, discoloration, and fiber deformation were not found to be showing apparent differences according to statistical analysis. The conclusions made by this research should be used with caution due to the small sample size.

TASER CEW distance determination for models X26P, X2, and TASER 7.

TASER weapons, classified as Conducted Energy Weapons (CEWs) are used by law enforcement as electrical, non-lethal weapons. A CEW's long distance method of deployment launches two barbed probes that embed into the target, before electricity is cycled from one probe to the other. The resulting muscle contractions help incapacitate the intended target. Currently, there is no research on the accuracy of variability of CEW probe spread in determining the distance of the shooter. Thus, in this study, a method of distance determination for TASER models X26P, X2, and TASER 7 was established to help estimate the relative locations of individuals during crime scene reconstruction. Each of four probe cartridge types were launched for six repetitions towards vertical cardboard targets from three different distances (n = 72). The probe spread on the targets was measured for each cartridge and plotted against CEW-To-Target (CTT) distance. Linear regression trendlines and standard deviations were generated for each cartridge type. Results demonstrated probe spread distances to be proportional to probe launch angles, and greater CTT distances resulted in greater standard deviation. Standard error of the estimate was calculated for all four linear regression equations and their ability to predict CTT distance when given probe spread measurements. The mean standard error values appeared acceptable for the X2 (0.460 m), TASER 7 CQ (0.273 m), and X26P (0.322 m) CEW models, while the mean error calculated for the TASER 7 Standoff model (0.846 m) was considerably greater. We expect our findings will help establish a reliable method of distance determination for CEWs, and perhaps with a larger sample size, more thoroughly examine the accuracy of the linear regression equations. CEW distance determination has the potential to provide support in contextualizing crime scene reconstruction with further research. By providing distance estimations alongside a standardized guide of error allowance, it would be possible to induce how far apart individuals were at the time a CEW was fired, within the calculated window of deviation, and in a statistical degree of confidence.

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 5 s 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.

An analysis of officer-reported TASER X2™ probe discharge effectiveness in the United Kingdom.

Conducted energy devices (CEDs) are designed to immobilise aggressive individuals through the application of an electrical discharge administered via probes fired at the subject. Although the discharge is intended to disrupt voluntary movement, CEDs have their limitations and several factors are qualitatively understood to adversely influence CED effectiveness. The introduction of the twin-cartridge TASER X2™ into UK policing in 2017 provided a unique opportunity to undertake a quantitative assessment of the factors modulating probe discharge effectiveness based on data reported by police officers firing the device operationally. The overall operational subdual effectiveness of the TASER X2™ was 68.5%. However, several factors were identified that could alter the likelihood of achieving subdual of the subject. The officer-reported data show that probe discharge was highly effective at subduing subjects when both probes had penetrated the skin, least effective when both probes were in clothing and confirmed the reduced effectiveness of narrow probe spreads. The most commonly cited reasons why probe discharge failed to subdue the subject were thick or loose clothing, probe misses and narrow probe spread. These findings, which are likely to generalise to other types of CED, may be used to inform tactics and training to optimise the likelihood of achieving incapacitation when probes are deployed, with benefits for the safety of both the police and the public. The findings may also assist investigations requiring the reconstruction of incidents in which probe discharge has been deployed.

Confusion between firearms and electrical weapons as a factor in police shootings.

Conducted electrical weapons (CEW) have risks including trauma associated with uncontrolled falls, probes penetrating the eye, and fume ignition. A lesser-known risk is weapon-confusion error with officers mistakenly discharging their firearm when they intended to deploy their electrical weapon. We searched for incidents of possible weapon confusion with the TASER® brand CEWs via open-source media, litigation filings, and a survey of CEW law enforcement master instructors. We found 19 incidents of possible CEW weapon confusion in law enforcement field uses from January 2001 to April 2021. We eliminated a case as not meeting our criteria for probable weapons confusion leaving 18 cases, thus giving a demonstrated CEW discharge risk of 3.9 per million with confidence limits (2.4-6.2 per million) by Wilson score interval. Ipsilateral carry of the weapons was historically correlated with increased risk vs. contralateral carry. Officer gender was not a predictor of weapon confusion. The psychological issues behind weapon confusion under stress are discussed. The concurrent carry of electrical weapons and firearms presents a very small but real risk of injury and death from confusion between an electrical weapon and a firearm.

Bone-Penetrating TASER Bolt: A Rare Case of Penetrating Injury to the Middle Phalanx of the Little Finger.

TASER© (Axon Enterprise, Scottsdale, Arizona) is a type of electric gun that delivers a sudden shock to temporarily disable a human subject. It is used by law enforcement, as well as civilians, worldwide. Despite its wide use as a "non-lethal" form of self-defence, it can lead to serious injuries. We are presenting a rare case report of a 28-year-old man who presented to our Plastic Surgery Trauma Service following a penetrating TASER bolt injury to the middle phalanx of his left little finger.

Medical Care in a Police Intervention with Conducted Electrical Weapons: Zaragoza (Spain) Fire Department Protocol.

In the last decade, conducted electrical weapons (CEWs) have become a new tool for law enforcement agencies as an alternative to firearms. They provide security in the intervention for both the police and the citizen and try to cause the least possible harm to the subject to immobilize.The health care providers who perform in joint actions with the police in which CEWs are used should be aware of how they work, risk groups, as well as the most frequent clinical effects associated with the application of electrical discharge, and the complications that can be produced according to the area of impact of the electrodes.For this purpose, the current medical literature was reviewed by consulting the main health care sciences database (PubMed) to determine the medical measures to be taken before, during, and after the use of these weapons. Also presented and shared is the Zaragoza (Spain) Fire Department protocol.

Aspiration-related pneumonia after Taser exposure - A multiple causations mechanism.

Arrest-related deaths in the context of Conducted Electrical Weapon (CEW) deployment are rare. The evaluation of such complex events is a challenge for the forensic scientist. We present a case of a 49-year old man, who was exposed to a Taser X26P during a confrontation with the police. He lost consciousness, vomited, aspirated and died after having been hospitalized for several days at the ICU. Based on the patient´s medical history, autopsy findings, witness testimonies, and reliable clinical and toxicological blood parameters, the most probable cause and mechanisms of his death are discussed. The present work demonstrates, based on one case report, the possibilities as well as limitations of forensic assessment in CEW-related deaths.

Police shootings after electrical weapon seizure: homicide or suicide-by-cop.

PURPOSE: Risks of handheld electrical weapons include head impact trauma associated with uncontrolled falls, ocular probe penetration injuries, thermal injuries from the ignition of volatile fumes, and weapon confusion police-involved shooting. There is also an uncommon but critical risk of a shooting after a subject gained control of an officer's electrical weapons. METHODS: The authors searched for police shooting incidents involving loss of control of TASER® weapons via open-source media reports, crowd-sourced internet sites, litigation filings, and a survey of Axon law-enforcement master instructors. RESULTS: The authors report 131 incidents of subjects attempting to or gaining control of an officer's electrical weapon from 2004 to 2020, 53 of which resulting in a shooting. These incidents demonstrated a risk of 11.8 shootings per million electrical weapon discharges (95% confidence limits of 9.0 to 15.1 per million by Wilson score interval). CONCLUSIONS: The use of electrical weapons presents a rare but real risk of injury and death from a shooting following a subject's attempts to gain control of the weapon.

Non-lethal weapon: Injury patterns and imaging correlates for firearm alternatives.

Law enforcement officers have adopted the use of non-lethal weapons to mitigate civilian casualties incurred by firearm use over recent years and decades. These weapons include, but are not limited to, TASER, beanbag rifles, pepper spray, tear gas, and Flash-ball guns. Nonetheless, severe injuries and even deaths do occur with use of these weapons, in rare instances. This review aims to comprehensively discuss these cases and associated injuries, as well as their according findings on imaging studies. It will also examine how often injuries occur in situations with non-lethal weapons.

Electrical weapons and rhabdomyolysis.

It has been suggested that an application of a conducted electrical weapon (CEW) might cause muscle injury such as rhabdomyolysis and an acute inflammatory response. We explored this hypothesis by testing the effects of electrical weapons on circulating markers of inflammation and muscle damage. In a prospective study, 29 volunteers received a full-trunk 5-s TASER® X26(E) CEW exposure. Venous blood samples were taken before, 5 min after, and at 24 h following the discharge. We tested for changes in serum levels of C-reactive protein (CRP), alkaline phosphatase (ALP), myoglobin, albumin, globulin, albumin/globulin ratio, aspartate and alanine aminotransferase, creatine kinase, total protein, bilirubin, and lactic acid dehydrogenase. Uncorrected CRP and myoglobin levels were lower in the immediate post exposure period (CRP levels 1.44 ± 1.39 v 1.43 ± 1.32 mg/L; p = 0.046 and myoglobin 36.8 ± 11.9 v 36.1 ± 13.9 µg/L; p = 0.0019) but these changes were not significant after correction for multiple comparisons. There were no changes in other biomarkers. At 24 h, CRP levels had decreased by 30% to 1.01 ± 0.80 mg/L (p = 0.001 from baseline). ALP was unchanged immediately after the CEW application but was reduced by 5% from baseline (66.2 ± 16.1 to 62.7 ± 16.1 IU/L; p = 0.0003) at 24 h. No other biomarkers were different from baseline at 24 h. A full-trunk electrical weapon exposure did not lead to clinically significant changes in the acute phase protein levels or changes in measures of muscle cellular injury. We found no biomarker evidence of rhabdomyolysis.

A comparison of three conducted electrical weapons in a surrogate swine cardiac safety model.

We used a previously described methodology in a swine model to compare the relative cardiac safety of the Axon T7 Conducted Electrical Weapon (CEW), released in October of 2018, to two prior generations of Axon CEWs to include the X2 and the X26E. A total of 5 swine (252 total CEW exposures) were tested by alternating the three weapons at each chest exposure location. Our testing, using systemic hypotension as the quantitative surrogate for cardiac capture, demonstrated that the T7 and X2 were not statistically different. Both were superior, in terms of reduced hypotension during exposure, to the X26E. This study is important as it demonstrates that the newly released weapon is non-inferior to the X2 and superior to the X26E using this surrogate safety model. It is also important because it is the first study to examine the cardiac effects of simultaneous multi-bay exposures. Our prior study compared the X2 to the X26E but examined only single bay exposures from the X2. Lastly, we feel we have improved the methodology for studying the comparative cardiac effects of CEWs.

A comparative study of conducted electrical weapon incapacitation during a goal-directed task.

Conducted electrical weapons (CEW) are ubiquitous in law enforcement given their unique ability to physically incapacitate violently resisting subjects. Early use of animal models to study CEW incapacitation effectiveness (e.g. porcine model with 4-limb strain gauges) proved to be poorly predictive of human incapacitation effectiveness. In a previously published human study, we developed a methodology for the prospective assessment of the incapacitation effectiveness of CEWs in highly motivated human subjects. Here we use this methodology in Part 1 to compare the incapacitation effectiveness of the newly released Axon® (formerly TASER® International) T(ASER) 7 to the TASER X26E, the "gold standard", and the TASER X2, a current model. The T7 has a new "adaptive cross-connect" technology that may improve incapacitation effectiveness in the scenario of small spreads between probe pairs, a common cause of weapon "failure" in the field. In Part 2, we use our methodology to test the functionality of the T7 cross-connect technology by comparing different bay and probe configurations. This is the first published study in the literature comparing different CEW models using this human model. For Part 1, 29 subjects completed the study and had data available for analysis. For Part 2, 21 subjects completed the study and had data available for analysis. The subjects were motivated to complete the task of reaching a suspended martial arts dummy 3.4 m (11 ft) away while being exposed "under power" to the CEW. In Part 1, subjects were assigned to 1 of 6 groups with probe spreads of 10, 20, and 30 cm (4, 8, 12 in). Subjects were exposed to a "control" CEW (either the X2 or X26E) and the T7 on alternating sides. Exposures with the X2 and T7 included 2 bay-exposures. In Part 2, 21 subjects were assigned to 1 of 5 groups of different T7 bay and probe configurations all with a theoretical effective spread of 30 cm (12 in). Subjects were rated on their progress towards successfully reaching the dummy and on the extent of limb incapacitation using a quasi-blinded expert-observer scoring panel based on high-speed video review. In Part 1, all CEW models achieved maximal or near-maximal subject control with the 30 cm probe spread. With probe spreads of 10 and 20 cm the pooled data showed the T7 to be superior to the X2 for goal achievement (p < 0.001) and limb incapacitation (p = 0.002) mostly driven by differences seen with the 10 cm spread (2-bay exposures). The T7 was non-inferior to the X26E. In Part 2, there was no statistical significance between the limb capture scores, but there was a statistically significant difference in goal scores. The results overall validate that the T7 CEW cross-connect feature performed as expected. The T7 adaptive cross-connect feature with two simultaneous deployed probe pairs demonstrated a significant improvement in incapacitation effectiveness compared to the current X2 CEW with two simultaneously deployed probe pairs. Small probe spreads are a common reason for limited incapacitation effectiveness in the field and this study suggests the T7 may offer an improvement in this scenario. The T7, with single-bay exposures, was non-inferior to the single-bay X26E.

Electrical weapons, hematocytes, and ischemic cardiovascular accidents.

BACKGROUND: There have been case reports following the use of a conducted electrical weapon (CEW) suggesting that these devices might affect coagulation or thrombosis in at-risk individuals. The aim of this manuscript therefore is firstly to explore this hypothesis by reviewing each of these cases and secondly to report the results of a prospective study exploring a priori the effects of electrical weapons on hematocytes in a group of human volunteers. METHODS: First, we systematically reviewed all cases of adverse outcomes following CEW discharge that could be due to an effect on coagulation or thrombosis, with particular focus on the clinical scenario and its relationship with the weapon discharge. Second, we assessed hematocyte levels in venous blood from 29 volunteers before, 5 min after, and 24 h after receiving a full-trunk 5-s TASER® X26(E) CEW exposure. RESULTS: Following extensive review of the literature, we found 3 relevant case reports of possible vascular thromboembolic clinical events after CEW exposure, specifically a case of ischemic stroke, and 2 cases of ST-segment elevation myocardial infarctions. Review of these published cases failed to establish a plausible linkage to the CEW beyond a temporal association with significant emotional and physiological stress from a violent struggle. Our prospective study of biomarker change following CEW discharge revealed acutely increased values for WBC (white blood cells), specifically lymphocytes and monocytes, and a raised platelet count. Neutrophil levels decreased as a percentage of WBC. While these changes were statistically significant at 5 min, all results remained within established reference ranges. At 24 h, all values had returned to baseline except total WBC which decreased to slightly below baseline but was still within the normal reference range. CONCLUSIONS: A review of clinical cases, of ischemic or thrombotic events revealed no direct association with the CEW discharge. A full-trunk electrical weapon exposure did not lead to hematocyte changes beyond normal clinically expected variations in similar acute response scenarios. The case report and biomarker data do not support the hypothesis that a CEW discharge is associated with changes likely to promote coagulation or thrombus formation.

The physiologic effects of a new generation conducted electrical weapon on human volunteers at rest.

Axon Enterprise, Inc. (Axon) released its newest generation conducted electrical weapon (CEW), the T7, in October 2018. In order to compare the effects of this new CEW to prior generations, we used our previously described methodology to study the physiologic effects of CEWs on human volunteers at rest. This was a prospective, observational study of human subjects consisting of two parts. Part 1 was testing a single cartridge (2-probe) exposure. Subjects received a 10-s exposure from the T7 to the back with a 30 cm (12 in.) spread between the two probes. Part 2 was testing a simultaneous two-cartridge (4-probe) exposure. Subjects received a 10-s exposure from the T7 to the back with two cartridges with a 10 cm (4 in.) spread between each probe pair. The probe pairs were arranged cephalad to caudal such that the distance between the top probe of the first cartridge and the bottom probe of the second cartridge was 30 cm (12 in.). Vital signs were measured immediately before and after the exposure. Continuous spirometry was performed. ECG monitoring was performed immediately before and after the exposure. Venous pH, lactate, potassium, CK, catecholamines, and troponin were measured before and immediately after the exposure, at 1-h post-exposure, and again at 24 h. 11 subjects completed part 1 of the study. 9 subjects completed part 2 of the study. No subjects had a dysrhythmia or morphology change in the surface ECG. There were no statistical changes in vital signs pre- and post-exposure. While subjects did not have a statistical change in spirometry parameters pre-exposure to exposure except for a small drop in PETCO2, there was an increase in minute ventilation after the exposure that could have several explanations. A similar pattern was seen with prior generation weapons. No subject had elevated troponin levels. Other blood parameters including venous pH, lactate, potassium, CK, and catecholamines had changes similar to prior generation weapons. Comparison of the data for the single-cartridge exposures against the simultaneous two-cartridge exposures yielded no difference in vital signs, but the minute ventilation was higher for the two-cartridge exposures. The blood data, where there was a difference, was mixed. In our study, the physiologic effects of the Axon T7 are modest, consistent with the electrically-induced motor nerve-driven muscle contraction, and were similar to prior generation weapons.