Trauma, Social EM, EMS

The Riot Trauma: What Injuries Should You Expect From Non-Lethal Police Weapons and Protests?

2020 has been quite the historic year for emergency medicine.

First, the novel coronavirus SARS-CoV-2 burgeoned into a global pandemic, overwhelming medical systems worldwide. As the country first began to ease restrictions, massive protests broke out after yet another avoidable and unnecessary death of an unarmed black man, George Floyd, who died after a white police officer knelt on his neck for nearly 9 minutes. Violent protests and more deaths ensued. The year continued with a drawn-out presidential election and another, potentially worse, wave of COVID-19 outbreaks.

Protests have become a more common occurrence.

Police respond with standard anti-riot measures, which often include a multitude of weapons, such as tear gas, pepper spray, rubber bullets, batons, riot shields, and TASERS®. On the other hand, weapons employed or improvised by the protestors, such as rocks, sticks, knives, guns, and Molotov cocktails add potential for increased severity and mortality from the use of said weapons. Emergency physicians are seeing an increase in riot-related injuries in their hospitals.

In this article, we will review some of the more common weapons in the riot police arsenal, as well as those used by protesters, and the injuries with which they are associated, in order to prepare our student doctors and emergency physicians in training to handle said patients.

While these riot-control agents are termed non-lethal or "less lethal" by their manufacturers and the police, it has the potential to result in significant harm. In some instances, it can lead to long-lasting disabilities or even death.2 As protests percolate throughout the country, an increasing number of news outlets are reporting serious injuries caused by exposure to these weapons. In Boston, the Emergency Department at the Massachusetts General Hospital (MGH) temporarily set-up a HAZMAT tent outside their hospital to help decontaminate and help treat people injured during these riots.1

Weapons Employed in Violent Protests

The Mucosal Irritants: Tear Gas & Pepper Spray

  • Tear gas: composed of chloroacetophenone (CN) and chlorobenzylidene malononitrile (CS) that is released into the air as fine droplets or particles.3 On exposure through skin, eye, or nasopharyngeal, these agents work as an irritant within seconds of exposure. The most common immediate symptoms seen include intense lacrimation, blepharospasm, and burning sensations in the oro/nasopharynx.4
  • Pepper spray: composed of oleoresin capsicum, an extract from peppers, a strong irritant to mucosal membranes. This extract, capsaicin, is the same chemical that is used as an adjunctive therapy for cannabinoid hyperemesis syndrome and in pain relief creams.10 For additional information, please see a dedicated article in this issue.

Clinical Pearls

  • Symptoms: Lacrimation, burning sensation of all mucosal surfaces, cough, nausea/emesis, vision changes/blindness
  • Treatment: Copious irrigation with water, pain control, consider ophthalmology consult if vision affected
  • Disposition: Likely discharge

Conducted Energy Weapons: TASER®
Stun guns like TASER® work a little differently but have an equal or stronger potential to cause serious injury. Also referred to as Conducted Energy Weapons (CEWs), they are the most common weapon used by law enforcement agencies to quickly incapacitate violent or combative individuals. These devices use a high voltage, low amperage current to override the subject’s ability to control their peripheral nervous system and thereby causing pain to induce compliance. Some models may have barbed probes attached to thin wires that can be shot at the subject from even 35 feet away to deliver a 5-second burst of stimulation.5 Patients with stun-gun injuries most commonly present to the ED with marks at the site of probe contact called signature marks.

The most common cause of injury from these devices including marks/puncture wounds from the probs, muscle strain and rhabdomyolysis, injuries from falls, ventricular fibrillation, and Excited Delirium Syndrome (ExDS).6 ExDS is an ill-defined syndrome that presents with agitation, hyperthermia, tachycardia, metabolic acidosis, and death. This condition is most commonly associated with the concurrent use of cocaine or other stimulants and CEWs.

Clinical Pearls

  • Symptoms: Muscle spasm, local wound, impaled barbs (skull/intracranial injury, eye injury, pneumothorax, pharyngeal perforation), testicular torsion, blunt trauma from falls, cardiac arrhythmias, unresponsiveness, sudden death11
  • Treatment: Treatment of all life threats, careful removal of barbs, wound irrigation, evaluation of Creatinine Kinase (CK) level, ED observation, EKG
  • Disposition: Depends on presentation, most presentations benign and dischargeable

Kinetic Impact Projectiles: Rubber Bullets
Similarly, kinetic impact projectiles (KIPs), commonly referred to as rubber or plastic bullets, are designed to incapacitate individuals by inflicting pain and sublethal injury. Some KIP guns target an individual with one projectile, while some release a group of multiple scattering projectiles.

There are more than 75 varieties of launchers and bullets sold all over the world, but they still face very limited regulation over the development of these weapons, and not much public information is released on the design or guidelines for use.7 Patients most commonly present to the emergency department with abrasions and hematomas, but when fired on in close range, patients can suffer traumatic brain injuries, bone fractures, and serious abdominal injury, including injuries to the spleen, bowel, and major blood vessels.

KIPs also have the potential to cause very severe injuries to the eyes, including orbital fractures, globe ruptures, and retinal damage. To this effect, the American Academy of Ophthalmology (AAO), has issued a statement strongly condemning the use of rubber bullets by domestic law enforcement to control and disperse crowds.

Clinical Pearls

  • Symptoms: Blunt force trauma to the affected area, in particular danger to eyes, trachea, blunt abdominal trauma
  • Treatment: Examination of affected area (ocular pressures, visual acuity), advanced imaging (CT scan) if abdominal trauma
  • Disposition: Unlikely to require admission, unless injuries found requiring admission

Burns and Explosions: The Molotov Cocktail
Another type of weapon commonly seen in protests, employed not by law enforcement but rather instigators of violence, is Molotov cocktails. Also referred to as a petrol bomb, alcohol bomb, or a poor man's grenade, this weapon is a simple, improvised incendiary device that can be made easily using household materials. It usually consists of a stoppered glass bottle filled with a combustible liquid, such as gasoline, high-proof alcohol, diesel, or jet fuel, and a fuel-soaked rag stuffed at the neck of the bottle. The instigator activates the device by lighting the fuel-soaked rag, which acts as a fuse, and then throwing the whole device at their target. When the bottle breaks on impact, spraying the fuel, the flame ignites it and produces a fireball explosion. Sometimes additives like motor oil, detergent, or rubber cement make the mixture stick better to the target or cause thick smoke.8

Patients exposed to these explosions may suffer severe, disfiguring second to third-degree burns, and need to be transported as soon as possible to the nearest Level 1 trauma or burn center for immediate care, after ensuring that the ABCs (Airway, Breathing, and Circulation) are intact.

Clinical Pearls

  • Symptoms: Lacerations, burns, potential for blunt trauma from falls or secondary trauma from projectiles
  • Treatment: Stop the burning process, wound care, trauma assessment for hidden injuries, estimation of burn area size and location, pain control
  • Disposition: Burn center evaluation for critical areas, depending on severity, admission to hospital

Blunt Force Trauma: Batons, Riot Shields, Rocks, Trampling etc.
Blunt trauma is another cause of injury. During protests, given the large number of people, additional dangers can exist. Aside from the discussed weapons, blunt force trauma covers the multitude of other injuries a bystander, media member, protestor or police officer can face. Riot shields are used by riot police to protect the officers from potential injury in case a protest becomes violent. They can be used as an offensive weapon to push a crowd into a specific direction, which could potentially cause trauma from direct force, or by destabilizing the crowd and causing trampling to occur. Batons are a common non-projectile defensive weapon that can inflict pain and if used with enough force, a bone fracture. Straight-stick batons often used by riot police are stronger and have a weight distribution that makes the striking edge create more kinetic force in order to have a maximal impact12.

Use of rocks and other projectiles by protestors can cause injury to any part of the body of an unprotected officer, hence why riot police are equipped with helmets, face shields, riot shields, and specialized riot uniform. Combined, these tools can create a wide variety of injuries, similar to assaults seen not so infrequently in the daily operations of a trauma center and most emergency rooms. Proper trauma assessment and availability of X-rays and CT imaging will be crucial to make a correct diagnosis and improve chances of survival.

Clinical Pearls

  • Symptoms: Fractures, contusions, lacerations, traumatic brain injury, blunt chest, and abdominal trauma
  • Treatment: Trauma assessment, appropriate imaging (X-Ray vs CT), pain control
  • Disposition: Admission vs discharge depending on severity of injuries, trauma center transfer if necessary


  1. Lima J. Mass. General deployed hazmat tent to treat tear gas victims as protests turned violent. WFXT. Published June 1, 2020. Accessed June 2, 2020.
  2. Resnick B. Rubber bullets may be "nonlethal," but they can still maim and kill. Vox. Published June 3, 2020. Accessed June 2, 2020.
  3. Centers for Disease Control and Prevention. Published April 4, 2018. Accessed June 3, 2020.
  4. Karagama YG, Newton JR, Newbegin CJR. Short-Term and Long-Term Physical Effects of Exposure to CS Spray. J Royal Soc Med. 2003;96(4):172-174. 
  5. Taser Injuries. In: Rosen P, Shayne P, Barkin AZ, et al, eds. 5-Minute Emergency Consult. Lippincott Williams & Wilkins; 2016. Accessed June 2, 2020.
  6. Mattu A, Chanmugam AS, Swadron SP, Tibbles C, Woolridge D, Marcucci L. Avoiding Common Errors in the Emergency Department. Wolters Kluwer Health; 2012.
  7. Haar RJ, Iacopino V, Ranadive N, Dandu M, Weiser SD. Death, injury and disability from kinetic impact projectiles in crowd-control settings: a systematic review. BMJ Open. 2017;7(12):e018154. 
  8. Helmenstine AM. What a Molotov Cocktail Is and How It Works. ThoughtCo. Published June 4, 2020. Accessed June 7, 2020.
  9. Robertson C, Rojas R, Taylor K. After George Floyd's Death, Toll Rises in Protests Across the Country. The New York Times. Published June 2, 2020. Accessed June 8, 2020.
  10. Moon AM, Buckley SA, Mark NM. Successful Treatment of Cannabinoid Hyperemesis Syndrome with Topical Capsaicin. ACG Case Rep J. 2018;5:e3. Published 2018 Jan 3. doi:10.14309/crj.2018.3
  11. Pasquier M, Carron PN, Vallotton L, Yersin B. Electronic control device exposure: a review of morbidity and mortality. Ann Emerg Med. 2011;58(2):178-88. 
  12. Anderson J. A Tribute To The Police Baton. Law Officer. Published October 11, 2017. Accessed June 8, 2020.

Related Articles

Caring for Homeless Populations in the ED: A Quick Guide

People experiencing homelessness commonly present to the emergency department for health care needs, and the ED plays a crucial role, as it serves as the first — and often the only — resource for acce

Health Policy Journal Club: A Study of Firearms Safety Education in the Pediatric Emergency Department

The pediatric emergency department is a unique setting in which educational interventions can reach a wide variety of people. The Health Policy Journal Club examines a study conducted to gauge the eff