Well, there you go. Shoot a tazer and run away, that gets you a shot in the back. Good luck with that.
You're leaving something out -- that the person that shot the taser took it from the officer after resisting arrest.
Police are going to be unable to do their jobs if suspects are allowed to resist arrest and take their weapons and use them against them.
There is no scenario where law and order can be maintained and that is allowed.