Tasers are effective, but not as effective as people think they are.

In a year long study by APM, they looked at the effectiveness of tasers made by Axon Enterprise Inc. from the largest police departments in the country. Of the fatal police shootings between 2015 and 2017, 250 fatal police shootings occurred after a taser failed to stop the suspect. In 106 of them, the suspect became more violent after being shocked. This suggests that the taser may have made the situation worse. Data from New York, Los Angeles, and Houston, revealed that the newer-model tasers are less effective than older ones. When analyzing data from 12 large cities, there was variability in its effectiveness due to differences in definitions and measurements.

For instance, the LAPD counted every trigger pull as a Taser usage. Other departments, such as the New York Police Department, only track each officer’s Taser, not trigger pulls. Consider an incident in which an officer shocks a suspect with a Taser three times, and the first two attempts fail to subdue the suspect, but the third one does. In L.A., the effectiveness rate would be 33 percent (three trigger pulls, one incapacitation); in New York, the effectiveness rate for the same incident would be 100 percent (one officer with a Taser, one incapacitation).

As can be seen, there is a lot of variability in the effectiveness of tasers across different states. In Los Angeles and Indianapolis, a taser failed to subdue someone at least 4/10 times. In total, 7/12 departments had a taser effectiveness rate below 70%.

There’s many reasons as to why tasers can fail, and one of the reasons for this is because police officers tend use their taser inside of 6 feet from the suspect. That’s closer than the recommended 7-to-15 foot range for the X2 and X26P tasers.

There are also other reasons as to why tasers may not work: “For the weapon to work, a lot has to go right. First, an officer must hit the target. Tasers simultaneously shoot two barbed darts attached to thin, electrified wires. Both darts have to hit the target to deliver a debilitating jolt of electricity. Each dart must strike within an inch or so of the skin — or better yet, penetrate it — to create a complete electrical circuit. If someone is wearing a heavy coat or loose clothing, the electricity may not arc into the body enough to lock up muscles.” So, tasers are not that effective as people believe it to be.

Looking at 5-years worth of data from Orange County and Orlando, Mesloh, Henych, and Wolf (2008) found that tasers were effective in 69% of first police iteration; meaning that it led to the suspect complying with the officer. When it came to the 2nd police iteration, tasers were effective in 68.1% of the 548 cases examined. In the third iteration, which tends not to become among police conflicts, 81.51% (n=221) ended successfully due to tasers. The 81.51% value could be an overestimate because “…it does not take into account the prior levels of force used and their cumulative effect on gaining compliance from the suspects. A suspect who has been ‘TASERed’ and sprayed with chemical agents and then wrestles with an officer may have become exhausted tired, disoriented and at that point either chooses to become compliant or is simply overpowered.” Tasers were more effective in first iteration than impact weapons (45%), compliance holds (16%), and takedowns (41%).

Sommers et al. (2018) looked at data from the Assessing Police Use of Force Policy and Outcomes funded by the NIJ. The first phase looked at a nationally reprehensive sample of 600 police departments; 2nd phase looked at 8 agencies that met a specific criteria and examined them over a 2-year period. When using probe mode on the taser (gives the officer the opportunity to maintain distance from an aggressive/threatening subject), tasers were effective in 74% of deployments when compared to it being effective in 88% of drive-stun cases (considered to be a “pain-compliance” technique, thus a lesser quantum of force than using the probes).

Of course, though, the effectiveness of probe-mode and stun-mode differ when looking at its effectiveness rate across suspect demographics. Among the full sample (n=918), probe-mode was less effective than stun-mode. Citizen weight was significantly correlated with a taser being effective, with the effectiveness of the taser increasing as weight also increased. Tasers were also less effective when used on males. Furthermore, tasers were more effective when the suspect was drunk or impaired. The effectiveness of tasers was not significantly associated with citizen aggressive resistance, height, age, and possession of a weapon and officer sex and experience.

Looking at probe-mode, tasers were less effective as a suspects height increased and became more effective as the suspects weight increased. In drive-stun mode (n=307), the only variable that was significantly correlated with taser effectiveness was the officer being male. Male officers were more likely to think that drive-stun mode was effective than female officers.

White and Ready (2017) give contrasting results to the study above by finding an effectiveness rate of 85%. Their study looked at 243 police departments across a 2-year period. Sommers et al. note limitations in their study: “First, the only personnel authorized to use a TASER were either assigned to the Emergency Services Unit (ESU) or a supervisory Sergeant. Second, TASER use was restricted to cases involving an emotionally disturbed person (EDP; e.g., displaying signs of mental illness) or someone appearing to be under the influence of alcohol or drugs presenting a physical threat. Third, the authors were only able to provide a descriptive analysis. Finally, while the authors acknowledged the TASER comes equipped with two potential modes of use (White & Ready, 2007, p. 173), their analysis did not examine how often each mode was used or whether compliance or satisfaction varied by mode type.” So, their study can not be used to show that tasers are highly effective as stopping suspects.

In summary, tasers do seem to be effective, but not as much as people think it is. It may be easy to say that an officer should’ve tasered someone instead of using deadly force, but this assumes that tasers can stop someone 100%. In reality, it’s not a guarantee. Compliance holds and takedowns also do not seem to be effective most of the time. The rate of taser effectiveness seems to be different based on region and suspect characteristics.

Some commentators have argued that, although police sometimes choose tasers over guns, they are racially biased against non-white suspects during the use of tasers (e.g. Lopez 2016).

Gau and Pratt (2009) found that the race of the suspect was not statistically significant. In other words, there is no racial bias in the use of tasers (see Engle 2001 for more).

We should not expect officers to even be racially biased in the first place. Firstly, in a non-simulation study, Wheeler et al. (2018b) remarked that blacks were less likely to be shot by the police. In looking at a simulation experiment, James, Vila, and Daratha (2013) remarked that cops were more likely to shoot whites and Hispanics rather than blacks. Cops were actually less likely to shoot a black individual, with the same holding true for unarmed suspects. There was a significant bias favoring black individuals in these simulations (B=0.31).  James, James, and Villa (2016) found that it took officers 1.09 seconds to shoot a white person compared to 1.32 seconds to shoot a black person; 14% of non-aggressing whites were shot compared to 1% of blacks. Corell et al. (2014) found no racial bias in police shootings