EDITORIAL: Tasers do affect the heart

May 3, 2008
The Globe and Mail

The case for a moratorium on police use of tasers in Canada has been immeasurably strengthened by a group of cardiologists and research scientists from the University of Toronto. They have exploded police and manufacturer claims that the taser does not affect the heart and therefore does not cause fatal heart problems. With taser use growing rapidly - the Mounties alone use them more than 20 times a week - a study by the University of Toronto researchers published in the latest issue of the Canadian Medical Association Journal should be bedside reading for legislators across Canada.

The issue of taser safety has been dominated by questionable science, a point made inadvertently by RCMP Commissioner William Elliott and Alberta Solicitor-General Fred Lindsay when they were voluntarily tasered on Thursday. The idea was to demonstrate that the electric stun gun's effects wear off almost as soon as the five-second zap ends. Step right up, ladies and gents. This is the science of the snake-oil salesman.

It would take more than one William Elliott for an effective experiment, and some of them would have to be on psychotropic drugs, or have a weak heart, or be in the anxious, sweating, breathless state police call "excited delirium."

Especially key, the gun's electrical charge would have to fall across the heart - what the University of Toronto professors call "the worst-case scenario" - and not just across the abdomen. And perhaps Mr. Elliott would afterward volunteer to have a 100-kilogram officer press a knee on his exhausted windpipe. (Respiratory exhaustion, not just heart problems, may be behind some of the taser-related deaths.) Then it would simulate the real world - the world in which Robert Dziekanski was fatally tasered by the Mounties at the Vancouver airport in October.

This is not to deny that the taser has benefits. In Brampton, Ont., this week, police saved a man's life by zapping him after he took a knife to his own neck. But police are permitted to use tasers where serious physical harm is not at issue, in part because they assume it is risk-free.

As the CMAJ study shows, this assumption is wrong. "New and independent research, both epidemiologic and biological, into whether tasers can kill is essential to settle this issue," the journal says in an accompanying editorial. The safety of tasers is a live issue.

Police don't believe it. To them, "tasers do not kill" has become a mantra; no matter how many people die (20 in Canada in the past five years), the mantra does not change. Not even Mr. Dziekanski's death prompted Mr. Elliott and his outfit to question the official line. On what does that line rest? Largely on a few studies of tasers' effects on pigs, and on coroners' inquests that have not directly blamed the taser for deaths.

But the CMAJ study from the University of Toronto researchers found major weaknesses in the pig studies, and clear evidence, both in a study they did on pigs and in pig studies they reviewed, that the heart could be affected when the gun's two barbs struck in such a way that the electricity passed through the heart (without the barbs actually penetrating the heart). In one study, researchers opened a pig's chest when it was zapped and observed that the heart was affected. The stun gun could cause the pigs to abruptly lose their blood pressure. Two pigs died immediately after the stun-gun discharge in the study. As for the inquests, the CMAJ makes no reference to them, but in an interview, co-author Paul Dorian said that "as a scientist, I'm sympathetic to the difficulty of ascribing cause with very limited information." His study concludes: "It is inappropriate to conclude that stun gun discharges cannot lead to adverse cardiac consequences in all real world settings." But that is exactly the police conclusion.

Whom is the public to believe, Mr. Elliott and Mr. Lindsay, who faced the taser's barbs, or medical scientists who specialize in the heart? The answer seems obvious.

Police guidelines for taser use are based on faulty assumptions. A temporary suspension of taser use would allow for those guidelines to be rewritten to reflect the weapon's real world risks.