"I felt there was no connection between the tasering and the death, because tasering is an external event and shouldn't affect the heart," he said. "Tasers are not a threat to life, that's my bottom line," Prof Williams said. ...[LINK]
Here's the problem Prof. Williams...
Taser International's official legal warnings [LINK] clearly state that tasers may affect the heart and may cause death.
"The risk of an ECD application having a negative effect on a person's heart rate and/or rhythm is not zero."
"Experts have indentified heart-to-dart distance as being a key determining factor in whether an ECD can affect the heart."
"When possible avoiding chest shots with ECDs reduces the risk of affecting the heart..."
"The ECD can produce physiologic or metabolic effects." and "Any physiologic or metabolic change may cause or contribute to death or serious injury."
"Reasonable effort should be made to minimize the number of ECD exposure and resulting physiologic and metabolic effects."
"The ECD can produce physiologic or metabolic effects, which include changes in: acidosis, adrenergic states, blood pressure... heart rate and rhythm..."
"Disregarding this information could result in death or serious injury..."
If not in the case of multiple taser hits (probably TWENTY-EIGHT), then when?
Your so-called expert opinion is rubbish and demonstrably so (see above).
Google also the taser's Curious Temporal Asymmetry.