Some technical details about tasers for those interested...
Note - this info goes way beyond what the manufacturer will admit, so the certified taser "experts" will not be aware of any of this.
The 1999-era M26 taser has a waveform that actually is a very short pulse of high frequency. These two characteristics actually did help to make it arguably reasonably "safe" with respect to direct cardiac effects.
Where it all went wrong was the 2003-era X26 taser. They changed the output waveform to also include a DC offset pulse that repeats at the 19Hz PRF. This component (the majority) of the output waveform is no longer short duration and no longer high frequency. They've unintentionally abandoned two key safety features for a trivial 5% increase in effectivity. The death rate PER DEPLOYMENT approximately doubled with the introduction of the X26 taser. The overall taser-associated death rate jumped from several per YEAR to about ten per MONTH.
Even one of the company's own experts has confirmed that the M26 has a wider safety margin than the X26. In other words, they've confirmed exactly what I've stated above.
For those that still refuse to accept the cause-and-effect relationship between being tasered and sometimes being dead, please respond to the taser's 'Curious Temporal Asymmetry' argument (Google the phrase).
For those that still feel that "tasers are safer than guns", please realize that tasers replace lower and safer forms of force in 99+% of all deployments. So your point is obviously true, but rarely applicable.
To be clear, the evil swirling around tasers is related to the waveform design error that makes the X26 far more potentially deadly than is reasonable, and the false claims by the manufacturer regarding the risk of death from the X26 taser. It's the false claims about safety that increase the usage pattern to the point where all sorts of people are being tasered, and the occasional non-violent subject is being killed by police (that have been fooled by the false claims).
I hope that this detail helps to clarify the complicated background of the actual problem with tasers.