I wonder if Melissa Northrup or Colleen Reed would agree with you. Both of these young ladies would be alive today if the death sentence against Kenneth McDuff had been carried out. Instead it was changed to life, which later qualified him for parole and he went on to murder these two young ladies, and is suspected of murdering others.
The record shows that life sentences do not keep criminals in jail for life, and violent criminals more often than not participate in further violence, often on a greater scale.
The death penalty drastically reduces recidivism every time it is carried out.
So is the problem that we are not killing these guys? Or that they are not serving life behind bars? Like I said, death is only warrented (in my opinion) if another life is at risk.