Why is "the question of the justice of the death penalty in principle" different from "the question of the justice of the death penalty in practice"?

* The penalty itself cannot be objected to discrimination or bias only the distribution of the death penalty can be objected to

An affirmative answer to one does not apply an affirmative answer to the other.

When we choose to adopt a policy, it doesn't mean we affir it even though it may sound just in principle, it may not be just in practice the way it is carried out

In principle it is just - in practice it is unjust