Madison: New research shows it is possible for a Taser to kill a pig. Therefore, in rare cases a taser could kill a human.

John Webster is a UW Professor of Biomedical Engineering. His research on pigs and tasers is not welcome among Taser manufacturers. "I think they'd prefer that I go away."

That's because research funded by Taser International says tasers can't kill, but Professor Webster says otherwise.

His study measured how close a taser needle needed to get to a pig heart to send it into shock. "We could take a normal taser dart and start it some distance away and gradually move it in towards the heart until the heart went into ventricular fibrillation."

Most taser research has used pig hearts because they're very similar to human hearts. The research found on average the needle needed to get within 17 millimeters of the heart to send it into shock. More research showed the average human heart is between 10 and 50 millimeters from our skin. "If you're emaciated it's more dangerous than if you're obese," says Webster.

Professor Webster is combining that info with reports of where police actually shoot the suspects. "From that estimate the probability that a taser could electrocute the heart. It will be a very small number."

Professor Webster says in less than 1% of all cases, a shot from a taser could be fatal. "It will be much less than 1%."

The Madison Police Department has 75 tasers in use, and they plan to acquire more. They were forced to revise their policies of when they use tasers last April, after an officer shot a teenager in the back in a school parking lot.

Despite finding that tasers can kill, Professor Webster is still a big supporter. "If I was a deranged person attacking a policeman with a knife, I would prefer the taser to a bullet. "I think tasers save lives, as contrasted with bullets."

The Madison Police Department is not commenting on the research, but do say they'll continue to use tasers as a non–lethal alternative to a gun.