Deputy Michael Medina, an eight-year HCSO veteran, deployed his Taser at the suspect [Charles Roy, 37] to try and subdue him, but the Taser was ineffective. At some point during the struggle, the suspect managed to take the Taser from the deputy. Deputy Medina, fearing for his safety, discharged his weapon striking the suspect once. ["shot and killed"]... [LINK]
So much for reliable effectiveness. Tasers are CLEARLY not always effective. This has been proven time and time again.
So what about safety? And by this I mean not only direct cardiac safety, but also the indirect safety of those that naively depend upon their weapons for protection.
This failure of a taser to be effective put the officer's life in danger and directly led to the sequence of events that ended with death of the suspect.