Death Penalty and Deterrence
Much of the current recent research suggests that the death penalty does not have a significant deterrent effect. One study by Sorenson and Wrinkle (1999) in Texas speculated that, if a deterrent effect did exist, it would be found in Texas because of the extreme numbers of death sentences and executions within the state. They not only found that there was no deterrent effect but that number of executions was unrelated to murder rates and felony rates as well. Another study by William Bailey (1998) in Oklahoma also found no deterrent effect; however, he did find that there was a significant increase in stranger killings and non-felony killings after Oklahoma resumed executions.
Moreover, Bailey conducted studies of several states, including Ohio, Oregon, North Carolina, and California and found no deterrent effect (Bailey, 1978, 1979, 1979, 1979). A study by Decker and Kohfeld (1990) used a 50-year time series from 1930-1980 to assess the effect of executions on murder rates in North Carolina, California, Texas, New York, and Georgia. Essentially, they found no deterrent effect in their analysis.
Most recently, according to a survey by the New York Times, states without the death penalty have lower homicides rates than states with the death penalty. Comparisons show that the average murder rate per 10,000 population in 1999 was 5.5 among death penalty states versus 3.6 among non-death penalty states (DPIC, 2001).
In California, instead of finding support evidence of a deterrent effect, Robert Harris found support for the brutalization effect (Harris, 1999). The brutalization effect suggests that executions increase crime rather than act as a deterrent. Harris found slight increases in homicides during the eight months following the execution. Another study, entitled The Capital Punishment Quagmire in America, examined differences in homicides and violent crime in 293 pairs of counties. They found no deterrent effect and higher violent crime rates in death penalty counties (Harries & Cheatwood, 1997).
A study by Radelet and Akers (1996) surveyed America's criminologists and discovered that most (87.5%) believe that the death penalty does, and can do, very little to reduce rates of criminal violence. In addition, they cited a survey by Peter D. Hart Associates, which found little support (26%) for the deterrence argument out of a random sample of police chiefs and county sheriffs throughout the Unites States.
An earlier study by Issac Ehrlich (1975) has played an important role in the public debate on the death penalty. Before this, most of the work on death penalty and deterrence was conducted by Thomas Sellin. In one particular study, Sellin examined groups of contiguous states, each group containing one state with capital punsishment ("retentionist") and one state without ("abolitionist"). His conclusion was that executions have no discernible effect on homicide death rates (McGahey, 1996). However, using an econometric technique to examine murder and execution rates in the U.S. from 1933-1969, Ehrlich found that capital punishment did in fact have a deterrent effect. He concluded that for each execution there was a deterrence of 7 to 8 murders (McGahey, 1996). This study received immediately criticisms from other criminologists. Passell and Taylor replicated the study and found when the period from 1963-1969 was excluded, the deterrent effect was statistically insignificant (McGahey, 1996). Bowers and Pierce found similar results and also questioned Erhlich's use of FBI rather than Vital Statistics data (McGahey, 1996). In 1985, Layson repeated Erhlich's study, making several improvements, including the use of Vital Statistics data, and confirmed findings of a deterrent effect (Layson, 1985). Finally, work by Brian Forst (1983) suggests that on balance the death penalty does not have a perceptible influence on the homicide rate.
