That's the question that Scott Henson at Grits for Breakfast asks to start a post. He is throwing the question back at the Texas legislature:
I'm watching the floor debate for HB 8 (aka "Jessica's Law") in the Texas House.
Bill sponsor Rep. Debbie Riddle thinks:
A) HB 8 will "send a message, loud and clear, to child predators" that will prevent their heinous acts,
B) "People who commit this kind of crime do not go around with the same rational reasoning process as you do." "They did not think about it," she said in response to criticisms that giving the death penalty to child molesters made them more likely to kill their victims.
So which is it? Will repeat child molesters learn of HB 8, quaver in their shoes, and change their dastardly ways, or will they not even be aware of the new law and disregard it entirely without drawing the obvious, rational conclusion under the law that they're better off if they murder the witness to the crime, in this case the child victim?
Lots of criminals commit acts that defy "reason" or "rationality" in a colloquial sense. Further, the empirical evidence on many people replying to deterrence incentives is pretty mixed (when the differences are small in sentencing or the probability of apprehension is low in particular).
However, I do agree with Scott about how defender's of the death penalty cannot have it both ways on this issue. This is what I wrote in my article on the subject:
Proponents of death penalty statutes for child rape have advanced three major arguments against the “freebie” theory. First, they argue that the theory “assumes that the rapist is contemplating the consequences of his act at the time of its commission.” This argument allows death penalty proponents to play both sides of the deterrence debate. For the death penalty to have a deterrent effect, a criminal must consider his or her actions in light of the consequences or deterrence fails to work. To then argue that the “freebie” theory is bankrupt because it assumes the criminal is thinking about those same consequences is contradictory nonsense. If a potential child rapist does not perceive the death penalty as a deterrent, then the primary argument in support of it is lost.
Like Scott, I'm astounded when people don't see this tension in their argument. If you want to justify the death penalty entirely for retributive reasons, then do it. But I don't think you can play both sides on the deterrence debate.