Steven Landsburg e-mail #1
> My beef? He bases the value of executing murderers
> on a "consensus" figure that estimates that executing
> a murderer deters ten murders. The problem is, it has
> not, to my knowledge, been empirically shown that the
> death penalty deters murders at all.
You seem to have completely missed the point here, which
is that I was trying to *over*estimate the deterrence
effect on murderers in order to bias things *against*
my desired conclusion. If the deterrent effect on
murderers is less than I said it was, then the argument
for preferring a vermiscripter-execution to a
murderer-execution gets stronger, not weaker.
In addition to being wrong on the logic, you're wrong
on the facts. The econometric literature on the
death penalty overwhelmingly supports numbers in the
vicinity of those I quoted. The biggest name in this
field is Isaac Ehrlich (a passionate *opponent* of
capital punishment, by the way) who, in 30 years of
working on this subject, consistently gets numbers
between 8 and 20 for the number of murders deterred
by an execution. For a balanced overview of the
literature, you might want to look at
The article by Levitt, et.al. finds very little
deterrent effect and should not be ignored, but it
also has to be weighed against literally hundreds
of other articles, almost all of which get numbers
in the Ehrlich range.
Then you ask:
> If Mr. Landburg were to accept that capital punishment
> deters no one, do you think he would change his stance?
I'm not sure what stance you mean. My stance in the
column was that *if* executing vermiscripters has a
sufficiently large deterrent effect compared to executing
murderers, then executing vermiscripters is better
policy than executing murderers. Obviously if capital
punishment deters nobody (including vermiscripters)
then neither policy is of any value.
I did say quite unambiguously in the column that
deterrence is, to my mind, the only possible justification
for capital punishment. If you're asking whether I
meant that, the answer is: Of course. Why else would
I have said it?
Steven E. Landsburg