The maker of Taser stun guns is advising police officers to avoid shooting suspects in the chest with the 50,000-volt weapon, saying that it could pose an extremely low risk of an "adverse cardiac event." The advisory, issued in an Oct. 12 training bulletin, is the first time that Taser International has suggested there is any risk of a cardiac arrest related to the discharge of its stun gun. But Taser officials said Tuesday that the bulletin does not state that Tasers can cause cardiac arrest. They said the advisory means only that law-enforcement agencies can avoid controversy over the subject if their officers aim at areas other than the chest. The recommendation could raise questions about whether police officers will find it more difficult to accurately direct the probes emitted by a Taser gun at a recommended body area in order to subdue a suspect. Taser officials say the change won't hinder officers' ability to use Tasers. In a memo accompanying the bulletin, Taser officials point out that officers can still shoot the guns at a suspect's chest, if needed. Police departments across the United States and in Canada and Australia reacted immediately to the bulletin, with some ordering officers to follow Taser's instructions and begin aiming at the abdomen, legs or back of a suspect. Officials with the Phoenix Police Department, one of the first in the country to arm all its officers with Tasers, said Tuesday that the new guidelines are being adopted by trainers who are reviewing departmental policy for possible changes. Critics, including civil-rights lawyers and human-rights advocates, called the training bulletin an admission by Taser that its guns could cause cardiac arrest. They called it a stunning reversal for the company, which for years has maintained that the gun was incapable of inducing a cardiac arrest. Scottsdale-based Taser insisted that the revision admitted no risk of cardiac arrest and served only as risk-management advice for law enforcement. In the past, Taser has cautioned that use of its stun gun involves risk inherent in police-suspect conflicts, including the risk that suspects fall after being struck by a Taser. "Taser has long stood by the fact that our technology is not risk-free and is often used during violent and dangerous confrontations," Taser Vice President Steve Tuttle said in an e-mail. "We have not stated that the Taser causes (cardiac) events in this bulletin, only that the refined target zones avoid any potential controversy on this topic." Taser's training bulletin states that "the risk of an adverse cardiac event related to a Taser. .. discharge is deemed to be extremely low." However, the bulletin says, it is impossible to predict human reactions when a combination of drug use or underlying cardiac or other medical conditions are involved. "Should sudden cardiac arrest occur in a scenario involving a Taser discharge to the chest area, it would place the law-enforcement agency, the officer and Taser International in the difficult situation of trying to ascertain what role, if any, the Taser. .. could have played," the bulletin says. The bulletin recommends that when aiming at the front of a suspect, the best target for officers is the major muscles of the pelvic area or thigh region. "Back shots remain the preferred area when practical," it says. For years, Taser officials have said in interviews, court cases and government hearings that the stun gun is incapable of inducing ventricular fibrillation, the chaotic heart rhythm characteristic of a heart attack. The guns are used by more than 12,000 police agencies across the country, including every major law-enforcement agency in the Valley. Many authorities credit the weapon with preventing deaths and injuries to officers and suspects. Advocacy groups such as Amnesty International allege that Taser guns are often used by police as a compliance tool on unarmed individuals who pose no deadly threat, who are drunk or on drugs and simply quarrel with officers. Mark Silverstein, legal director of the Colorado American Civil Liberties Union, who has tracked Taser issues for years, said the bulletin means that police departments should now be asking questions about liability and reconsider how the stun gun is used. "This is further evidence that law-enforcement agencies need to stop and ask if they have been sold a bill of goods," he said. "This (training) bulletin confirms what critics have said for years: that Taser has overstated its safety claims.. .. (It) has to be read as if Tasers can cause cardiac arrest." Since 2001, there have been more than 400 deaths following police Taser strikes in the United States and 26 in Canada. Medical examiners have ruled that a Taser was a cause, contributing factor or could not be ruled out in more than 30 of those deaths. The training bulletin is drawing significant attention in Canada, where controversy erupted after the 2007 death of a Polish immigrant at Vancouver International Airport. The man stopped breathing after being shocked five times by Royal Canadian Mounted Police officers. A Canadian government investigation in July concluded that Taser stun guns can cause death, spurring law-enforcement agencies across the country to put severe new restrictions on how and when police there can use the weapons. In view of Taser's bulletin, the Mounties revised policies to urge officers to avoid firing at suspects' chests. Guidelines: You share in the USA TODAY community, so please keep your comments smart and civil. Don't attack other readers personally, and keep your language decent. Use the "Report Abuse" button to make a difference. 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