It marks the first time that Taser International has suggested there is any risk of cardiac arrest related to the use of its 50,000 volt stun guns.
As part of a revised training manual issued Monday Oct. 12, the Scottsdale-based taser maker advised law enforcement not to shoot the stun guns at a suspect's chest.
Taser critics called it a stunning reversal by the company, which for years has maintained that the weapon was incapable of inducing a cardiac arrest.
"It's a sea change, a passive acknowledgment that Taser has indeed been overconfident about its claims of safety," said Mark Silverstein, legal director of the ACLU of Colorado. "It underscores the question marks that have been adding up along with hundreds of bodies."
Amnesty International says more than 350 people in the U.S. have died after they were shocked with Tasers, and that in 50 of those cases, medical examiners cited a link between Taser shocks and death.
But Taser officials said Tuesday the recommendation means only that law-enforcement agencies can avoid controversy if their officers aim at areas other than the chest. The manual says to avoid chest shots "when possible" and "unless legally justified."
"There is no significant shift," Taser spokesman Steve Tuttle said in an e-mail. "Just a slight change by literally a few inches when intentionally targeting the preferred target zone." Tuttle added, "studies continue to demonstrate that the Taser carries a lower risk of injury than traditional force options, leading to lower officer injury rates and safer communities."
Tasers are used by 14,200 law enforcement agencies throughout the United States. Human rights groups have long said that Tasers cause heart attacks, but Tuttle said there have been 96 lawsuits that the company won or judges dismissed.
He said Taser has lost just one case, which is under appeal.