No sir, I want justice.  A person who kills someone for the fun of doing so, a person who kills for no reason other than the joy of killing, a person who kills in cold blood, merits a punishment that fits the crime: a life for a life. This isn't rocket science, sir, and I am not going to allow you to turn in to rocket science. 

Vengeance would be demanding the life of the killers family and friends, and taking their life while forcing the killer to watch--then taking his life.

The above being said: I am not saying the death penalty is absolutely necessary to ensure justice. I am saying that it isn't incompatible with Christianity or the pro-life position. I am also saying that Pope Francis is incorrect to suggest that the death penalty involves an intrinsic moral evil and that his predecessors were wrong to apply it.