Taser studies flawed, epidemiologist says

May 24, 2008
Neal Hall, Vancouver Sun

The studies that have been done to determine the risks of the Taser stun gun are flawed, a Vancouver epidemiologist told a provincial Taser inquiry Friday.

"I don't think you can extrapolate the results to the real world," said Dr. Keith Chambers.

He recommended that until more research is done to resolve the many unanswered questions about the risks and benefits of the weapon, limits on its use, with standardized guidelines, should be put in place.

Chambers said the "genie is already out of the bag," meaning it may be too late to conduct proper controlled trials of the weapon. But outcomes could be tracked with better systems of data collection.

He said one of the problems with existing research studies is that the circumstances in them don't occur in the real world. Most of the people on whom Tasers were tested were healthy volunteers who received a single five-second electrical jolt, which incapacitates a person by contracting muscles.

The earliest Taser research involved testing on pigs.

"Animal studies and volunteer studies don't support the real world and don't measure the magnitude of the harms and benefits," said Chambers, an epidemiologist who designs medical research studies. "In my mind, we have no idea of the relative risk in a large population due to Taser use."

In the studies that have been done, the sample sizes were too small to obtain reliable results, he said. For example, one study used only 66 people. "It's a huge problem, the sample size," he told inquiry commissioner Thomas Braidwood, a retired judge.

He noted that there have been seven Taser-related deaths in B.C., a relatively small number, given the growing use of the weapon by police. "You've got to have large numbers [of people tested] because the event rate is so low," he said. He suggested a proper sample size for a study would be 50,000 subjects.

The inquiry heard from a number of municipal police chiefs and RCMP commanding officers who support the use of the Taser. They said that, used properly, it can save lives and reduce injury to officers and suspects.

More than 300 people in North America, including 19 in Canada and seven in B.C., have died after being jolted by a Taser.

Tom Smith, chair of Taser International, the weapon manufacturer, based in Scottsdale, Ariz., told the inquiry that Tasers are like air bags: They save lives but occasionally contribute to a death.

"Are Tasers risk-free? No, they cause people to fall down," Smith told the inquiry, pointing out that Tasers save 70 lives for every life lost.

But several presenters at the inquiry called for a moratorium on Tasers pending further independent research. One was Murray Mollard, executive director of the B.C. Civil Liberties Association.

He said Friday that government control over Taser use by police in B.C. has been an "utter failure," since "police forces sold the technology to [their] political masters and the general public as a weapon that would be used as a substitute for the use of firearms, thus saving lives."

Back in 2000, when Tasers were first used in B.C., the civil liberties association supported their use based on the premise that they would be an alternative to deadly force. Since then, Mollard observed, the weapon has become "the most controversial use-of-force tool employed by police."

His organization is urging the provincial and federal governments to commission new independent research to determine the risks of using Tasers on people with heart disease and mental illness, and the risks of multiple shocks from the stun gun.

He suggested there be standardized regulations on when Tasers can be deployed, as well as uniform training.

He would also like to see the B.C. government publish detailed annual statistics on Taser use "to provide the public with a meaningful ability to understand the circumstances and justification" for the use of the weapon.

The second phase of the inquiry, expected to take place in the fall, will focus on the events surrounding the death of Robert Dziekanski at Vancouver International Airport on Oct. 14, 2007.

After a long flight from Poland, the 40-year-old man wandered around a secure area of the airport for seven hours, looking for his mother, who lives in Kamloops. He appeared tired and disoriented and began behaving erratically.

Dziekanski, who spoke no English, was eventually confronted by police, shocked twice with a Taser and restrained by RCMP officers. He died minutes later.

The B.C. government ordered the Braidwood inquiry to probe Taser use after the Dziekanski incident.