Mark Pazin, Merced Co. Sheriff: "Richard Abston had a medical condition over the past years and in fact had open heart surgery and had a device in him that was an internal defibrillator."
An internal defibrillator, like the one in this picture, is used to correct an irregular heart beat by delivering electrical shocks when needed. Marina Holmes of the American Red Cross says the device combined with meth can be fatal.
Marina Holmes, Red Cross Health & Safety Dir.: "You are affecting the rhythm of the heart, and so that acceleration is going to cause probably the defibrillator not to work at best. At worst, it can cause death."
Holmes says she has not seen studies about the impact a taser can have on a defibrillator, but Police Chief Russ Thomas says the weapons are not known to be deadly.
Russ Thomas: "I don't know of any proven history where a taser has been the cause of death."
Authorities say the toxicology report not only explains Abston's death, but also his erratic behavior in the last moments of his life. Drivers who saw Abston on the Highway say he had a crazed look and was laughing as he swerved his truck toward them.
Mark Pazin: "Not only was he a danger to himself, but obviously a danger to the motoring public."
Sheriff Pazin says the autopsy results will now be turned over to the district attorney's office for a final evaluation.