Why did this person deserve to get stunned, let alone die?

A teenager carrying a Bible and shouting "I want Jesus" was shot twice with a police stun gun and later died at a St. Louis hospital, authorities said.

In a statement obtained Tuesday by The Associated Press, police in Jerseyville, about 40 miles north of St. Louis, said 17-year-old Roger Holyfield would not acknowledge officers who approached him and he continued yelling, "I want Jesus."

Police tried to calm the teen, but Holyfield became combative, according to the statement. Officers fired the stun gun at him after he ignored their warnings, then fired again when he continued struggling, police said.

I'll have more on my issues with how police handle the use of deadly force a little later.  Stun guns are seen by many police forces as an easy way to subdue people now, and I think it could turn out to be a large problem.  Stun guns are not "non-lethal".  They are, in law enforcement vernacular, "less than lethal".  That means that while often times they don't kill, they can kill.  Unfortunately, the companies which market these weapons play down those risks, and it's having deadly consequences.  The recent case here in Wisconsin is yet more proof.  During that incident, a man was shot multiple times (up to 6) with a taser, and later died.

While police may be understandably excited about having a less than lethal alternative to firearms when dealing with a suspect, my fear is that police are also more inclined to use these weapons when normally they wouldn't use any sort of force, simply to make it easier to subdue someone who is unruly.  Given the danger, is that an appropriate use of force?  I would say no.  I am not suggesting that tasers be removed from police arsenals, but I think much more stringent training and regulations need to be created to govern their use.  Incidents like this prove that they are severely lacking.