That's typical of the "logic" that religious people use. Typical in that it's not at all logical.
I'm an atheist and I recognize that the death penalty has failed every test. Punishment is meant to deter future crime and the statistics are clear; the death penalty does not deter crime (Somebody is going to make an idiotic comment on this. I'm going to allow that individual to identify himself). It's a failure because it costs many times more money to execute a person that to keep them imprisoned for life. It's immoral because the justice system is imperfect, making execution of innocent people inevitable.
We could streamline the judicial process to a point that it would make the death penaly an effective deterrent, but that would certainly lead to the execution of more innocent people.
So for all of those rational and logical reasons, atheists oppose the death penalty.
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