Mission Statement - De-Spinning the Pro-Taser Propaganda

Yeah right, 'Excited Delirium' my ass...


The primary purpose of this blog is to provide an outlet for my observations and analysis about tasers, taser "associated" deaths, and the behaviour exhibited by the management, employees and minions of Taser International. In general, everything is linked back to external sources, often via previous posts on the same topic, so that readers can fact-check to their heart's content. This blog was started in late-2007 when Canadians were enraged by the taser death of Robert Dziekanski and four others in a short three month period. The cocky attitude exhibited by the Taser International spokespuppet, and his preposterous proposal that Mr. Dziekanski coincidentally died of "excited delirium" at the time of his taser-death, led me to choose the blog name I did and provides my motivation. I have zero financial ties to this issue.

Saturday, January 23, 2010

Taser pros and cons - do the math

SFGate - (Unlike many departments, San Francisco police officers are not equipped with Tasers...) One-third of shootings by San Francisco police over a five-year period might have been avoided had officers been equipped with less-lethal options such as Tasers, a police study suggests. ... The study focuses on the 15 shootings by San Francisco police officers from 2005 through August 2009 involving serious injury or death. Eight of the targets were killed, and seven were wounded. ... In five of the....shootings, the study suggests, officers needed something to incapacitate a suspect not armed with a gun "in order to stop the immediate threat." The suspects had knives or had charged the officers. [LINK]

At first glance, the above-quoted study appears to provide support for the introduction of tasers. In fact, that conclusion is paper thin, and upon further analysis it's clear that the study actually supports maintaining the status quo (no tasers).

What follows is just a bit non-intuitive. I hope that I've explained it clearly enough that readers will be able to follow. Feedback welcome.

First, note that this study confirms what has been noted previously in this blog. When police shoot a subject with a normal gun (bullets), the actual death rate (typically assumed to be 100% by many) is actually only about 50%. In this study, the death rate was 8 of 15 (53%, or perhaps even lower depending on how one interprets what's included in the denominator). Many pro-taser folks will base their arguments on the false assumption that "every taser deployment is a life saved". Even ignoring every other aspect of the larger debate, such claims are immediately off the mark by a ratio of about 2-to-1 based on this single factor alone.

(And although serious injuries are important, they're not even on the same page as death. If you don't mind, let's sort out the death issue before being distracted by discussions of injuries. I'd love to get the debate moved along to that point, but we're not there yet. Not even close.)

So the five cases where tasers might have actually been useful to prevent a police shooting, it would have actually saved a life (on average) in about 50% or three (3) of those cases, generously rounding up. So far, based on this study covering five years in the life of a fairly-large city, we're actually talking about actually saving perhaps three (3) lives.

But we're far from having a complete analysis.

The next factor to be considered is the relatively high rate that tasers are ineffective. One report had the effectivity rate at about 70%, or rate of deployment failure or taser ineffectivity of about 30%. I've seen worse figures mentioned, but the 30% is probably more indicative. Again, one can argue about the exact rate, but this seems to be a reasonable adjustment to apply.

The taser ineffectivity rate of about 30% means that if San Francisco had been equipped with tasers since 2005, and had attempted to use their tasers in those five appropriate incidents during that same period, then their tasers would have been ineffective about twice. Using their implied logic, that "tasers save lives", then the five (5) attempted deployments would actually be, due to the approximate 30% rate of taser ineffectivity, much closer to three (3) effective deployments.

Combining the two previous points, the three (3) lives actually available to be saved, combined with the 30% ineffectivity rate, means that tasers might actually save two (2) lives in San Fransisco during the five year period covered by the study.

To review what's been covered so far: five (5) opportunities to use a taser (per the study), but bullets are actually about 50% lethal (per the study), less 30% for the rate of tasers actually being effective (per reports), is about two (2) lives that might have been saved, over five years, by a city-wide roll-out of tasers in San Fransisco.

It's really important to clarify that the news report of this study was speaking of five (5), but using self-evident adjustments, the actual lives that might be saved is probably about two (2).

The above paragraphs also reveal the next important factor. Do you really think that San Fransisco police, assuming that they were all (!) equipped with tasers so that they'd actually be available to save lives at each of these opportunities, do you really think that the entire police force (combined!) would use their tasers only those five times, or only about ONCE PER YEAR for the entire force?

Obviously, such an implicit assumption would be insanity-in-a-can.

It is self-evident that tasers, when introduced, are used far far and away more often than those ONCE PER YEAR live-saving opportunities.

In fact, as has been shown by all the taser usage statistics I've seen, tasers are actually used about one hundred times as often as police have used their guns. In other words, if they had been equipped with tasers since 2005, they would have deployed tasers about 1500 times during that 5-year period. Almost every single day on average.

Feel free to argue about the precise rate of taser overuse, but it would be insanity to claim that tasers would only be used about once per year by a major police force. The overuse ratio of tasers is just as likely 200x as it is to be 50x. As a round number, 100x is good.

The next directly-related question is the risk of death with taser use.

Taser International likes to claim, or perhaps they like to pretend to claim, that the risk of death is close enough to zero that it can be rounded to zero.

Well, 0.49% risk of death per deployment could be "rounded to zero." Since they're systematically unwilling to discuss actual numbers, let's use this one to see where it leads...

0.49% of the estimated 1500 taser deployments would still be about seven (7) taser deaths!

And seven (7) is much greater than the two (2) lives we were (realistically) trying to save.

[Technical note for those interested. This mathematical situation is very similar to the issue of false positives in medical diagnostic tests of rare conditions. In short, when you think that you're presented with what is a rare condition, and you over-prescribed diagnostic test with their own non-zero false positive rate, then the cure can - quite literally - be much worse than the disease. This is a well know issue in medicine.]

The actual rate of taser "associated", caused or contributed death is still an open question, but the assertions and implications made by Taser International that the taser are incapable of ever causing death have been roundly rejected by any observers that are both informed and honest.

(For reference, refer to the recent Maryland Attorney General's report on tasers that concluded that concluded that Taser International has "significantly" understated the risks of taser use.)

It can be seen that their claims of safety, precisely bounded by 0.49% (can be "rounded to zero"), are well within the range that their product - even purely mathematically - can cause more deaths than it prevents. Any reasonable set of numbers results in the conclusion that tasers bring about as many, if not more, problems as they might actually solve. Note the keyword "actually", because the slick-talking stungun salesmen will be happy to test the limits of your skepticism.

But, even assuming the numbers are close, there's still a karmic balance problem.

Presumably and hopefully, most of those eight fatal police shootings were morally, ethically and legally justifiable. Or, if they were not, then hopefully the police formally apologized and provided a reasonable package of compensation to the families.

With tasers, because they're actually used far more often in cases where lethal force would not be appropriate, they impose excruciating torture and random death on non-violent citizens. That's evil on its face.

And in cases where death results, the evil false assurances of safety are used to protect profits and prevent justice. Compensation is rarely provided, for all the complex reason that we've previously explored. That's another layer of evil.

In my opinion, it's not just a numbers game. One does not balance the karmic books by saving the occasional life of someone that might be in a situation where potentially lethal force is a perfectly ethical response, while hundreds of other non-violent citizens are being taser tortured and exposed to a unjustifiable risk of death.

See also:

Attn: San Francisco Police Chief George Gascón

Gascón's Golden Gate Tasergate

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