Sorry, it's you who have failed. I'm still waiting on any evidence from you that there has been trend towards increasing unjustified taser use.
To help you out, I did a little looking myself. I found one study that applies, by UCSF in the American Journal of Cardiology.
http://www.sciencedirect.com/scienc...serid=10&md5=13b115e1aefc6f2654e19cd7083a4a3a
Unfortunately, you have to pay for the full article. I'm not willing to fork over $32 at the moment. Given your job, you should have ready access to the whole thing, as any news outlet should have subscriptions to this stuff. Could you grab the whole thing for us? Here's the abstract:
It's an interesting study in comparison to your claim. It basically claims the exact opposite of the trend you claim. It claims that the first year they're deployed, there's teething pains, but after that all goes back to normal. However, it's not a complete match: you were talking about justification on use and this study is talking about injuries.
It's a small study and not entirely conclusive. I'd really like to see the whole article to see how the numbers really play out, since the result is not intuitive to me. It's final claim is that tasers are currently ineffective, which is a surprising claim and contrary to what I would have expected.