The death of Mr. Dziekanski at Vancouver airport was a terrible tragedy and certainly the police action as seen on video seems unwarranted and excessive given that Dziekanski was distraught unarmed and not even threatening the police. Certainly there should be an investigation. See the Star article.
However, there is the larger issue whether tasers should be allowed at all. It seems that since they are considered as a non-lethal alternative to guns perhaps they are used more than they should be and without regard to the fact that they are not non-lethal at all. Since 2003 there have been 18 taser related deaths in Canada.
See the CBC map.
Maybe it is better that this so-called non-lethal alternative should be retired from use. It is too easy to regard the taser as a harmless means to subdue someone without the police being hurt but this does not take into account the danger to the person being tasered.