What I'm reading on the internet is a great deal of misbelief that such an accidental confusion was possible. Some are pointing to a potential coverup. Some are pointing to extreme failure in training.
I haven't been able to find an up to date statistic of the number of people killed by tasers, but it's well over 1000.
We have GOT to change how policing is done.
Such a confusion is most certainly possible. It's human nature and I do not believe training can overcome it. If anything, more training probably makes it
more likely as the motions are more ingrained and thus the error is less likely to be realized before it's too late.
However, I don't believe your figure for the number "killed" by tasers. The problem is people who are nuts on drugs. In the old days the only way to subdue them was batons. Sometimes they died, this was attributed to damage from being subdued. Then the taser came along--they could be subdued without being beaten. Yet some would simply die afterwards anyway. This strongly suggests that it's something about the body--and this makes perfectly good sense, also. Many examples of rebound reactions exist, push something away from the normal and the body pushes back. Take drugs, quit, you get withdrawal symptoms. (In the case of alcohol they can even be fatal.) This even exists with legally prescribed stuff--there are drugs that can have bad reactions from suddenly stopping, there are a few that can have lethal reactions to suddenly stopping.
Push the body crazy hard with drugs, the body of course pushes back. When the drugs wear off you come crashing down--it certainly looks like this is a scenario where the counter swing can be lethal. We will almost certainly never know, though, as there's no remotely ethical way to test it.