Taser International has admitted in a training bulletin that repeated blasts of a taser can “impair breathing and respiration“. Also, on Taser’s website it is stated that, for a subject in a state known as “excited delirium” (a controversial term in itself), repeated or prolonged stuns with the Taser can contribute to “significant and potentially fatal health risks“. In such a state, physical restraint by the police coupled with the exertion by the subject are considered likely to result in death or more injuries. Critics alleged that electroshock devices can damage delicate electrical equipment such as pacemakers, but tests conducted by the Cleveland Clinic found that Tasers did not interfere with pacemakers and implantable defibrillators.
It is assumed that tasers as well as all other high voltage stun devices can cause cardiac arrhythmia in susceptible subjects, possibly leading to heart attack or death in minutes by ventricular fibrillation (which leads to cardiac arrest and if not treated immediately to sudden death). People susceptible to this outcome are sometimes healthy and unaware of their susceptibility.
Critics argue that although the medical conditions or illegal drug-taking among some of the casualties may have been the proximate cause of death, the electric blast of the taser can significantly heighten such risk for subjects in an at-risk category. This suggests that tasers and other electroshock weapons would be dangerous to use on people with certain medical conditions and yet, since police officers will typically not know about a person’s medical history or possible drug use, this entails a risk of death with virtually any suspect.
While they are not technically considered lethal, some authorities and non-governmental organizations question both the degree of safety presented by the weapon and the ethical implications of using a weapon that some, such as sections of Amnesty International, allege is inhumane. As a consequence, Amnesty International Canada and other civil liberties organizations have argued that a moratorium should be placed on taser use until research can determine a way for them to be safely used. Amnesty International has documented over 245 deaths that occurred after the use of tasers. Police sources question whether the taser was the actual cause of death in those cases, as many of the deaths occurred in people with serious medical conditions and/or severe drug intoxication, often to the point of excited delirium.
Critics of taser use, however, argue that “excited delirium” is not a valid medical term and is not listed in the Diagnostic and Statistical Manual of Mental Disorders. Tasers are often used as an alternative to talking and waiting for a suspect to comply, striking the suspect with a baton or shooting them with firearms. Only the later two of which have a much higher chance of serious injury and death than the taser, even using the highest estimates of possible taser-related deaths. The term “less-lethal” is being used more frequently when referring to weapons such as tasers because many experts feel that no device meant to subdue a person can be completely safe. The less-lethal category also includes devices such as pepper spray, tear gas, and batons. One problem when comparing the Taser to other forms of force is that no precise statistics are kept in the U.S. on policing related deaths or the use of excessive force. In 2001, the New York Times reported that the U.S. government is unable or unwilling to collect statistics showing the precise number of people killed by the police or the prevalence of the use of excessive force. There has been one case report in the medical literature of a person suffering spinal fractures after being shocked by a taser. The U.N. has declared: “TASER electronic stun guns are a form of torture that can kill.”