Earlier this year, in Louisville, Kentucky, police officers shocked a man with a stun gun so many times that his children asked whether he was dead, a Justice Department investigation found.
Police and law enforcement have been using Tasers, known generally as stun guns, since 1974 as a safer alternative to guns. But risk of death is still a concern. There have been more than 1,000 reports of deaths involving a Taser or another conducted electrical weapon (CEW).
“A Taser, while intended to be nonlethal, can still incur serious effects, which in some cases, can be life-threatening,” especially for those with a heart condition or who are on drugs that affect the cardiovascular system like cocaine and methamphetamine, said James Giordano, a professor of neurology and biochemistry at Georgetown University Medical Center and an expert on military medical ethics.
About 90 percent of law enforcement in the US issues Tasers, and given that there are roughly 18,000 law enforcement agencies, that corresponds to more than 140,000 Tasers nationwide.
Police have been known to shock people as young as 11 years old and as old as 75, so it’s important to know how these devices affect the brain and body.
A quick note before we get into it: Taser is a brand name for a specific type of CEW. Put another way, all Tasers are stun guns, but not all stun guns are Tasers. Some of the research cited below involved stun guns, and not Tasers specifically.
1. Stun guns make your muscles seize up like a Charley horse
Stun guns are meant to safely stop people in their tracks.
Taser’s common X26 model administers a shock of about 1.9 milliamperes, according to the Institute of Electrical and Electronics Engineers – well below the 10 milliamps needed to cause a severe electric shock but still enough to have an effect.
“Basically, Taser energy weapons send a signal to your muscles telling them to flex,” or seize up, Amy Nguyen, the chief safety officer at Axon, which manufactures Tasers, said.
This induces a state called neuromuscular incapacitation, which hijacks the communication link between your body and brain, making it difficult to make any voluntary movements.
2. People who have been shocked say it hurts a lot
Strikes from stun guns “cause severe, uncontrollable contractions of your muscles, which are very painful,” Dr. Jonathan J. Rasouli, a neurosurgeon with Staten Island University Hospital, said, adding: “This is what gives Tasers their incapacitating power and can stun an individual quickly and reversibly.”
One person described the pain as the sensation of his brain shaking “like a peanut in a jar.”
“If you were to shake that jar a hundred times as fast as you can and multiply that by a thousand,” the person told Reuters.
3. An electrical shock may severely affect the heart
Being exposed to electricity can cause ventricular fibrillation, the most serious type of irregular heartbeat.
A study attributed at least some of the deaths following a Taser X26 shock to cardiac arrest, which can be a consequence of VF.
An electrical strike from a stun gun could “lead to disruptions in heart function that can range from moderate to severe and possibly fatal,” Giordano said.
For most people hit by stun guns, there are no cardiovascular effects, Rasouli said.
“Most studies have shown that 50,000 volts, the voltage seen on most commercial Tasers, is safe to the heart,” he said.
Still, with the reports of cardiac arrest after strikes from CEWs, Rasouli said, “scientists are not exactly sure yet” about the likelihood of a stun gun affecting your heart.
4. Strikes can temporarily affect memory and cognition
After being hit with a stun gun, you might not be able to recall short-term memories. And you may have trouble processing new information, which could last for up to one hour, one study found.
“Since a Taser shock is an incredibly stressful and painful experience, there can certainly be neurocognitive side effects,” like trouble finding words or processing information, Rasouli said.
This temporary effect on memory has led to a push for police to delay questioning or the reading of the Miranda rights to people who have recently been shocked, until they have the chance to recover cognitively.
5. Getting shocked may also be emotionally or psychologically jarring
While there’s limited research on the psychological effects of CEW jolts, being shocked may contribute to trauma. The physical and emotional pain of a strike is an “objectively traumatic event,” Giordano said.
This is an important area of research, since many people who’re hit with stun guns are already in a high-stress situation and experiencing emotional distress. Rasouli said more research was needed on how a strike might contribute to mental illness long term.
6. Sharp probes can lead to puncture wounds, scrapes, and bruises
In one study involving 1,201 cases of shocks from stun guns against criminal suspects, about 83 percent of people reported a mild injury of superficial puncture wounds, making these wounds the most common injury associated with Tasers.
Many Tasers and some other CEWs have two probes with pointed metal barbs that shoot out and puncture the skin. While the wounds are typically minor, at least one person reported he needed surgery to remove a barb.
Scrapes and bruises are also possible since many people fall over after being hit by a CEW. A study from 1987 found that 38 percent of people who were shocked reported lacerations or scrapes.
8. Rarely, stun guns can severely harm kidney function
Very rarely, stun guns can cause a serious condition called rhabdomyolysis, AKA rhabdo, which can be fatal.
“Rhabdomyolysis occurs when muscle tissue is overstimulated, becomes over contracted, and components of muscle protein are released into the bloodstream,” Giordano said.
Those proteins can damage kidney function and even induce kidney failure. Rhabdomyolysis is treatable, but without medical attention, it can be fatal, Giordano said.
The same study that found puncture wounds to be a common injury also found evidence for rhabdomyolysis in one out of 1,201 people hit with stun guns.
9. In a few cases, electrical shocks have caused the testicles to twist up
Another study from the ’80s on CEW injuries found that 0.5 percent of people studied experienced testicular torsion, or twisted testicles. That can happen to men when their muscles contract severely, Giordano said, even if a Taser doesn’t hit the pelvis directly.
During testicular torsion, one or both testes twist on their spermatic cords, tissue that sends blood to the scrotum. That can cut off blood flow to the testicles and cause the testicular tissue to die if blood flow isn’t restored within six hours.
So testicular torsion isn’t just very painful but also a medical emergency, though it’s rare for people who are shocked by a stun gun.
“While possible, such injuries are not common when an individual is Tased,” Giordano said.
10. You usually regain muscle control quickly
The electrical pulses from a Taser strike last only five seconds. After that, most people return to their normal muscle function right away.
“Recovery from the incapacitation is instantaneous,” Nguyen said.
Of course, you’d still need to cope with secondary injuries like bruises, cuts, memory impairment, or, sometimes, long-term emotional or psychological trauma.
11. But you’ll probably be sore afterward
Some people who are hit with CEWs experience muscle soreness for a few days after the fact. This happens for two reasons, Giordano said.
First, your pain receptors and nerve endings are overstimulated by the electrical shock, making them more sensitive. Second, the strong muscle contractions can induce the same sort of muscle fatigue you might experience after hitting the gym.
You can usually treat it with heat, a cold pack, or over-the-counter painkillers.
This article was originally published by Business Insider.
More from Business Insider: