Your statistics are off. According to the linked story:
"Chief Beck says on average, LAPD will have at least one Taser use a day without any serious health issues. Out of those hundreds of cases, Chief Beck says LAPD sees about three Taser-related fatalities each year".
So, used once per day by LAPD and 3 deaths per year = 0.8% probability of death.
Anecdotally, there are about 50 taser deaths per year, in the US, at the hands of police:
http://electronicvillage.blogspot.com/2009/05/taser-related-deaths-in-united-states.html
The problem is that no official national data is collected on deaths at the hands of the police; either shootings, tasers or by other means. Nor do we know how many times officers discharge a firearm or a taser. So, we do not know definitively what the death rate is for either means of force.
Courts have generally held that tasers fall into non-lethal force; however, they can still constitute excessive force under the 4th Amdt.
Bryan v McPherson US Court of Appeals 9th Circuit.