Tasers can cause permanent damage, and the documented cases range from spinal fractures to total blindness to fatal brain injuries from falls. Most people who are hit by a Taser walk away with nothing worse than small puncture wounds and sore muscles, but the medical literature contains enough serious outcomes to make the “non-lethal” label misleading. The risk depends heavily on where the darts land, how long the device is activated, and the physical characteristics of the person on the receiving end.
What the Device Actually Does to Your Body
A Taser fires two barbed darts connected to the device by thin wires. Once both darts make contact, the device delivers short, low-energy electrical pulses designed to stimulate motor neurons and cause temporary, involuntary muscle contraction throughout the body.1PubMed. Physiology and pathology of TASER electronic control devices That is why a person who gets Tased goes rigid and falls: the electrical signal hijacks the body’s own motor-control system, overriding voluntary movement for the duration of the discharge, typically five seconds per trigger pull. The muscle contractions are powerful and affect the entire body simultaneously, which is the root cause of many of the injuries described below.
Bone Fractures From Muscle Contraction Alone
One of the more surprising permanent injuries linked to Taser use is spinal fracture. The forced contraction of the muscles running along the spine can be violent enough to compress vertebrae, even in otherwise healthy people. A case report described a law enforcement officer who sustained an acute thoracic vertebral compression fracture during a routine training exercise after a single five-second Taser discharge.2PubMed. Thoracic spine compression fracture after TASER activation Researchers compared the mechanism to compression fractures that occur during seizures, where the same kind of sudden, massive contraction of the paraspinal muscles overwhelms the structural capacity of the bone.3PubMed Central. Thoracic Compression Fracture as a Result of Taser® Discharge
These injuries are not limited to the spine. Electrical shock injuries can cause joint dislocations and fractures elsewhere in the skeleton because the involuntary muscular force generated by the current can exceed what the bones and connective tissue can handle.4The Journal of the American Osteopathic Academy of Orthopedics. Taser-induced Bilateral Femoral Neck Fractures: A Case Report A compression fracture in the spine or a fractured hip can require surgery, weeks of immobilization, and chronic pain. For older adults or people with conditions that weaken bone, the risk is considerably higher.
Rhabdomyolysis and Kidney Damage
Beyond fractures, the intense muscle activity triggered by a Taser discharge can break down muscle tissue itself. When muscle fibers are damaged on a large enough scale, proteins from the damaged cells flood the bloodstream and can clog the kidneys. This condition, rhabdomyolysis, is well recognized in medicine from other causes like crush injuries and extreme exertion. At least one case report documented severe rhabdomyolysis and kidney failure after a Taser exposure in a person who had none of the usual risk factors, suggesting that the Taser discharge alone was enough to trigger the breakdown.5PubMed Central. TASER Electronic Control Device-Induced Rhabdomyolysis and Renal Failure: A Case Report Kidney damage from rhabdomyolysis can be permanent if not treated quickly, and it is especially dangerous because the person and even the medical team may not immediately connect the kidney failure to the Taser exposure.
Heart Rhythm Disruption
The cardiac risk from Tasers has been the most debated topic in this field for years. Modeling of the thorax shows that muscle tissue and the chest wall divert roughly 90% of the current away from the heart, producing electrical fields in the cardiac muscle well below the levels needed to disrupt its rhythm.6PubMed. Cardiac Safety of Conducted Energy Devices: Electrophysiological mechanisms, risk assessment, and forensic interpretation That is the basis for the claim that Tasers are generally cardiac-safe. But the same research acknowledges that rare probe alignments directly across the heart, or a person with a thinner-than-average chest wall, can bring the current dangerously close to the threshold where it could trigger an abnormal rhythm.
This is not just theoretical. A published case report describes a young man shot in the chest by a Taser who arrived at the emergency department in ventricular fibrillation, a chaotic heart rhythm that is fatal without immediate treatment.7PubMed. Ventricular fibrillation in a man shot with a Taser Taser’s own manufacturer has recommended that the devices not be aimed at the chest, though the company stopped short of stating that a chest discharge definitely causes arrhythmia. For practical purposes, the risk is low but real, and people with thin builds, pre-existing heart conditions, or implanted cardiac devices face a different risk profile than the average person.
On the topic of implanted devices specifically, one study tested the effects of Taser discharges on pacemakers and implantable defibrillators. The electrical parameters of the devices were not significantly different before and after the shocks, and no malfunctions occurred.8PubMed. Do electrical stun guns (TASER-X26) affect the functional integrity of implantable pacemakers and defibrillators? However, the implanted defibrillators did detect the Taser pulses as a rapid heart rhythm, which means in a real-world scenario they could attempt to deliver an unnecessary shock therapy of their own. That interaction is something emergency physicians need to be aware of, even if the Taser discharge itself does not physically damage the implanted device.
Brain Injury and Seizures
Taser darts are fired at high velocity and are barbed to anchor into the skin. When a dart strikes the skull, the consequences go beyond what anyone expects from a “non-lethal” weapon. A case report describes a police officer who was accidentally hit in the upper back and occiput (the back of the skull) by a Taser during a foot chase. Within seconds, he collapsed and experienced a full tonic-clonic seizure with loss of consciousness.9PubMed Central. Generalized tonic-clonic seizure after a taser shot to the head A more recent case documented a Taser dart that actually penetrated the skull and caused a brain injury with subsequent seizures, directly contradicting the common assumption that the darts cannot penetrate bone.10PubMed. TASER dart causes penetrating intracranial injury
These cases are rare, but they matter because seizures triggered by electrical injury to the brain can cause lasting neurological effects. A penetrating skull injury from a Taser dart is functionally similar to other low-velocity penetrating head wounds, which carry risks of infection, chronic seizure disorders, and long-term cognitive impairment. The medical literature treats these as serious traumatic brain injuries, not incidental injuries from a “less-lethal” device.
Eye Injuries and Blindness
The eye is one of the most vulnerable targets for a Taser dart, and the data here is surprisingly detailed. A comprehensive review identified 28 cases of penetrating eye injury from Taser probes across roughly 3.4 million field uses, putting the demonstrated risk at about 1 in 123,000 deployments. Of those 28 cases, 18 resulted in total unilateral blindness or surgical removal of the eye.11PubMed. Eye injuries from electrical weapon probes: Incidents, prevalence, and legal implications That means the majority of people who took a Taser dart to the eye lost the eye entirely.
One particularly well-documented case involved a 47-year-old woman struck by a Taser dart that penetrated through the central cornea. Even after surgical repair, her final visual acuity in that eye was reduced to perceiving light without being able to tell where the light was coming from, which is functionally near-total blindness.12The Journal of Emergency Medicine. Catastrophic Globe Disruption as a Result of a TASER Injury And it is not only direct hits that cause problems. Researchers have also reported diffuse retinal injury from non-penetrating Taser darts that struck near the eye, suggesting that the electrical current itself can damage the retina even when the dart does not physically enter the globe.13PubMed Central. Diffuse retinal injury from a non-penetrating TASER dart
A 1-in-123,000 chance may sound small, but it is worth putting in context. No one who is being Tased gets to choose where the darts land. The face and eyes are in the line of fire whenever a Taser is deployed against someone facing forward, and unlike other body regions, the eye has essentially zero tolerance for a high-velocity barbed projectile.
Fatal Falls After Being Tased
Some of the most devastating permanent outcomes from Tasers are not caused directly by the electrical current but by the uncontrolled fall that follows. When your muscles lock up involuntarily, you have no ability to brace yourself. You fall the way a felled tree falls. If your head strikes concrete or another hard surface, the result can be a catastrophic traumatic brain injury. A study examining deaths following Taser use identified 16 probable cases of fatal brain injury caused by falls after electronic control, out of roughly 3 million field uses.14PubMed. Fatal traumatic brain injury with electrical weapon falls The average age of the people who died from these falls was higher than the typical person subjected to Taser use, and shots to the back appeared to carry a higher risk of a fatal fall.
Non-fatal fall injuries include broken wrists, fractured hips, dental injuries, and facial fractures. These secondary traumas are easy to overlook in discussions about Taser safety because they are technically fall injuries rather than electrical injuries, but the fall is a direct and foreseeable consequence of the device’s intended function. You cannot incapacitate someone’s muscles without also incapacitating their ability to protect themselves from hitting the ground.
Fire and Burn Injuries
The electrical arc from a Taser can ignite flammable substances, and the consequences have been severe enough to kill. Testing has shown that the arc from a Taser is capable of igniting petrol vapors on a fuel-soaked person, and in enclosed spaces, the device can trigger a vapor explosion.15PubMed. The ignitability of petrol vapours and potential for vapour phase explosion by use of TASER® law enforcement electronic control device This is not a hypothetical risk confined to the laboratory. A review of real-world incidents confirmed 6 fatal and 4 major non-fatal burn injuries out of roughly 3.17 million field uses, with the ignition sources including cigarette lighters in pockets, gasoline, recreational inhalants, and aerosol body sprays.16PubMed. Fatal and non-fatal burn injuries with electrical weapons and explosive fumes
Severe burns are among the most debilitating permanent injuries a person can sustain. They often require extensive skin grafting, cause lifelong scarring and pain, and carry serious risk of infection. The fire risk is particularly troubling because the person being Tased frequently has no control over the flammable substances on or near their body, and the officer deploying the device may not know those substances are present.
When Prolonged or Repeated Exposure Raises the Stakes
Most of the safety data on Tasers is based on the assumption that a person receives one standard five-second discharge. In practice, officers sometimes activate the device multiple times in quick succession, and each additional cycle compounds the physiological stress. Animal studies have shown that extended or repeated Taser exposures can produce significant elevations in blood potassium, acidosis, and muscle-protein release into the bloodstream.17PubMed. Deaths in custody: are some due to electronic control devices (including TASER devices) or excited delirium? A single limited application appears to have only transient metabolic effects, but stacking multiple discharges shifts the risk profile considerably.
This is especially relevant in custody situations where a person is agitated, physically exerting themselves, and then receives multiple Taser cycles. The overlap between the physiological effects of extreme exertion and repeated Taser exposure makes it difficult to determine after the fact which factor caused what damage.18PubMed. Pathophysiologic changes due to TASER® devices versus excited delirium: potential relevance to deaths-in-custody? Both pathways lead to the same dangerous endpoints: elevated potassium, acidic blood, muscle breakdown, and cardiovascular stress. When these layers stack, the risk of cardiac arrest and organ damage climbs steeply.
Why the Medical Record Is Probably Incomplete
One significant problem with understanding the full scope of permanent Taser injuries is that the documentation is inconsistent. An examination of 184 autopsy reports from deaths following Taser exposure found that a large portion of the reports were missing basic information about the police encounter and the Taser deployment, including how many times the device was activated, where the darts struck, and how long each cycle lasted.19PubMed. Forensic reporting of TASER exposure: An examination of situational and exposure characteristics If even fatal cases have incomplete records, non-fatal injuries that result in long-term disability are almost certainly undercounted. There are no national standards in the United States that require consistent documentation of Taser-related injuries, which means the true incidence of permanent damage is unknown and likely higher than what the published case reports suggest.
This gap has practical consequences. If you or someone you know sustains an injury during a Taser deployment, detailed medical documentation immediately after the event is crucial. Emergency departments do not always think to check for rhabdomyolysis, spinal compression fractures, or retinal damage in the context of a Taser exposure. The injury patterns are unusual enough that physicians may not connect them to the Taser unless specifically prompted.
Who Faces the Highest Risk
Certain groups are at elevated risk for permanent injury from Taser exposure, though the evidence base is thinner than it should be. People with thin chest walls face a higher probability of cardiac current reaching dangerous levels.6PubMed. Cardiac Safety of Conducted Energy Devices: Electrophysiological mechanisms, risk assessment, and forensic interpretation People with osteoporosis or low bone density are more susceptible to the compression fractures caused by involuntary muscle contraction. People under the influence of stimulants may already have elevated heart rates and blood pressure, making the cardiac stress of a Taser discharge more dangerous. Older adults are both more likely to have thinner bones and more likely to sustain serious head injuries from falls. And people with implanted cardiac devices face the potential for their defibrillator to misinterpret the Taser signal and deliver an inappropriate shock.8PubMed. Do electrical stun guns (TASER-X26) affect the functional integrity of implantable pacemakers and defibrillators?
None of these risk factors are visible to an officer in the field, and none of them are screened for before a Taser is deployed. The device is designed as a one-size-fits-all tool for incapacitation, but the body on the receiving end is anything but one-size-fits-all. The gap between the assumed risk and the actual risk for a specific individual can be enormous, and that gap is where permanent injuries happen.