Deterrence

On Friday, I linked to a Wall Street Journal OpEd on deterrence.  Also on Friday, the New York Post carried the OpEd by John Lott,  "Death Penalty's Deadly Vacation," that purported to demonstrate a deterrence effect to capital punishment.

Karl Keys has a response in "They seem to be getting desperate."  Here's a selection with a table:

Let me not bloviate. The table below shows the data for the years 1995 until 2006. Even the most rudimentary examinations shows that the murder rated dropped uniformly in states with and without the death penalty. The data also shows even as executions dropped the murder rate stayed level. The table also shows that the murder rates in abolitionist states continued to fall throughout the period the murder rate of retentionist states stalled.

I have also included in the chart the Houston MSA (The Houston Metropolitan Statistical Area includes Harris County and surrounding areas in Texas in its media market) as it is the singularly largest executing area of the country and IF a deterrent effect is observable it should be observable there.

Year	Houston MSA Murder	National Murder	Executing States	Nonexecuting States	Abolitionist States	Harris MSA Executions	National Executions
2006	9.6	5.7	—-	—-	3.1	9	53
2005	9.1	5.6	6	4.4	4	6	60
2004	7.8	5.5	6	4.2	4	9	59
2003	8	5.7	6.2	4.4	4.1	8	65
2002	8.4	5.6	6.1	4	4.3	4	77
2001	8.3	5.6	6.1	4.3	4.2	4	61
2000	7.7	5.5	5.9	4.3	4.2	7	85
1999	8.1	5.7	6.1	4.4	4.6	6	98
1998	8.8	6.3	6.8	4.6	4.6	5	68
1997	9.1	6.8	7.4	5.1	5	11	74
1996	9.8	7.4	8	6	5.4	1	45
1995	12	8.2	8.9	4.8	6.8	4	56

I should note that Prof. Harcourt in Asylum to the Prison: Rethinking the Incarceration Revolution, 84 Texas L. Rev. 1751 (2006). and over at SSRN, “From the Asylum to the Prison: Rethinking the Incarceration Revolution - Part II: State Level Analysis:” looks at data sets going back to the 1930s.

Also, thanks to Ron Tabak for distributing the Post OpEd.

 

Comments

[JohnLott]

Here are responses to Keys post that he hasn't really responded to:

1) It would be nice if you noted that not all states with the death penalty actually use it. If you were to breakout the states by the rate that they use the death penalty, you would find that states when states use it more frequently they have a larger drop in murder rates. This is in fact what the studies that find a drop indeed look at.

2) The Harcourt paper is unusual in that it doesn’t separately take into account the impact of imprisonment and locking people away for mental health reasons.

3) About 3/4’s of all the research by economists find that increased execution rates reduce murder. The few studies that don’t include strange measures of the execution rate (e.g., executions per person in prison instead of per murder).