A Rochester man died after being subdued with a Taser on Sunday. Details about Richard Davis' exact cause of death have yet to be released, but local groups and witnesses have voiced concerns about the role the instrument may have played in his death.
Conductive Energy Devices, or CEDs, have been involved in over 500 deaths since 2001, according to Amnesty International, but whether or not they are the cause of those deaths is a disputed issue.
Many articles suggesting the dangers of CEDs point to a single paper in the American Heart Association journal Circulation, by Doctor Douglas Zipes. Zipes says he studied eight cases where a Taser was used directly against a person's chest and says the electricity caused cardiac arrest.
"Tasers deliver electricity to stun an individual, and we know in cardiology that electricity delivered to the chest wall through the skin can affect the heartbeat."
Zipes says this process is called cardiac capture, and it is used in defibrillators and pacemakers.
"If the Taser electricity captures the heart then it can rev the heart rate up to such rates that the heart can no longer maintain normal, organized contraction."
But Zipes will be the first to tell you that he is considered to have a potential conflict of interest. As a Distinguished Professor and Researcher of Cardiology at Indiana University School of Medicine, he's been paid to give expert testimony in cases involving CEDs and heart failure.
Steve Tuttle is a spokesperson for Taser International. He says the eight cases that Zipes details in his paper do not make up a comprehensive study.
"There is no cause and effect in a case series, you're just simply pointing out unique and novel situations."
Tuttle says people who the police use Tasers against might be compromised in some ways that weaken their heart - maybe they are on drugs or they are strained from the intensity of the situation.
Even so, Tuttle says they do recommend officers aim their devices below a target's chest.
"That accomplishes several things. One, it keeps the probe away from the heart so nobody could conjecture that the Taser was a causality of any cardiac issues. Number two, this also increases a greater effectiveness."
Tuttle says it also reduces the risk of hitting someone in the throat or eye.
Ultimately, it is up to the department to set their own protocols for the CEDs they use. RPD Chief Mike Ciminelli says they plan to release details about the department's Taser use in the near future.
Taser international estimates their CED is used in the field almost 1000 times per day.
