On the other hand, I know exactly how I feel about this:
Killing another human being is wrong. Period.
No, I don't care that you've killed another human being because he killed another human being, because killing another human being is wrong.
No, I don't care that he went through the system - the system is created by humans, who are fallible. Therefore, the system is fallible, and mistakes can be made (which is what fallible means). Death is not undoable, and therefore a mistake leading to death cannot be corrected. Besides, killing another human being is wrong.