Since the Government launched its new ‘e-petitions’ site
this week there has been a surge in debate surrounding the death penalty – one of the most popular topic areas in the site’s first few days.
Newspapers, bloggers and other commentators quickly joined the debate with both sides of the argument quoting different statistics at each other in attempts to gain the upper hand.
One of the most contentious debates surrounds the deterrent effect of the death penalty. The anti-capital punishment campaigning group‘Reprieve’
, for instance, quote figures which suggest that countries with the death penalty tend to have higher homicide rates. They claimed last year:
“The five countries in the world with the highest homicide rates that do not impose the death penalty have nearly half the number of murders per 100 000 people than the five countries with the highest homicides rates which do impose the death penalty (United Nations Development program)”
The validity of using static murder rates as a means of determining the penalty’s deterrent effect is of course open to question.
While the figures could lead one to conclude that capital punishment is ineffective given the high murder rates in countries where it is legal, it could also be the case that the countries which do practice it would have much higher homicide rates if the death penalty were not in place.
Homicide rates have, however, proven to be a common measure of deterrence in the United States
, and have also been the basis of detailedresearch
on the matter.
In light of this, Full Fact decided to test the claim that countries with the death penalty tend to have higher homicide rates on average, using the latest United Nations data
The five countries with the highest homicide rates who also have legal capital punishment are Jamaica, El Salvador*, Guatemala, Trinidad & Tobago and Lesotho, with an average between them of 46.6 homicides per 100,000 people.
Meanwhile the five such countries who have abolished the death penalty for all crimes are Honduras, Venezuela, Colombia, South Africa and Ecuador, with average homicides of 41.3 per 100,000 people.
This, however, is far more than half the number of murders amongst the five countries with the penalty still in force.
Taking average homicide rates of all countries with and without the death penalty, the difference is marginally greater, with 36.7 homicides per 100,000 amongst those with the penalty compared to 27.4 amongst those which abolished it.
Finally, Full Fact calculated if there was any correlation between countries imposing a death penalty and having higher homicide rates, as the averages would suggest.
Ranking all 147 countries for which data was available in terms of homicide rate, and comparing this to whether the penalty existed or not, yielded a weak positive correlation of 0.2.**
This means that there is some correlation between imposing the death penalty and having higher homicide rates, but this correlation is in fact weak to bordering on insignificance.
So it seems that those using global homicide rates to support either side of the death penalty debate need to justify why their findings are statistically significant. Our calculations suggest there isn’t enough proof that capital punishment is or isn’t an effective deterrent to murder.
*El Salvador impose the penalty only in exceptional cases.
**Correlation derived using Spearman’s Rank Correlation Coefficient using binary ranking for death penalty imposition by country.
Deterrence: States Without the Death Penalty Have Had Consistently Lower Murder Rates
|Murder Rate inDeath PenaltyStates*
|Murder Rate in
(click on year to see the murder rates and calculations involved in this analysis, provided by David Cooper)
* Includes Kansas and New York in the years after they adopted the death penalty, 1994 and 1995 respectively. New Jersey and New York ended the death penalty in the latter part of 2007 and will not be counted as death penalty states in 2008.
Populations are from the U.S. Census estimates for each year.
Murder rates are from the FBI’s “Crime in the United States” and are per 100,000 population.
The murder rate for the region (death penalty states or non-death penalty states) is the total number of murders in the region divided by the total population (and then multiplied by 100,000)
In calculations that include Kansas and New York, Kansas is counted as a death penalty state from 1994 and New York from 1996, since New York’s law did not become effective until September, 1995.
Murder Rates in Death Penalty States and Non-Death Penalty States
The murder rate in non-death penalty states has remained consistently lower than the rate in states with the death penalty, and the gap has grown since 1990.
STUDIES COMPARING STATES WITH THE DEATH PENALTY AND STATES WITHOUT
Michigan Lawmakers Reaffirm State’s Longstanding Ban on Capital Punishment – In a vote upholding the state’s longstanding abolition of the death penalty, Michigan lawmakers refused to support a measure that would have put capital punishment before state voters in a referendum. The vote fell 18 short of the 2/3 required for passage. During a lengthy House debate regarding the bill, Representative Jack Minor (D-Flint) told his colleagues that studies show crime rates are lower in states without the death penalty. He noted, “The death penalty’s not a deterrent. In fact, the figures would suggest it’s just the opposite.” Other opponents of the measure stated that “revenge” would not help victims’ families. Michigan has not had the death penalty for 158 years, and voters have not addressed the issue since its abolition was included in the 1963 revision of the state constitution. Michigan is one of 12 states in the U.S. that does not have a death penalty. (Michigan Live, March 19, 2004) The state was the first English speaking government in the world to ban the practice.
States Without the Death Penalty Have Better Record on Homicide Rates – A new survey by the New York Times found that states without the death penalty have lower homicide rates than states with the death penalty. The Times reports that ten of the twelve states without the death penalty have homicide rates below the national average, whereas half of the states with the death penalty have homicide rates above. During the last 20 years, the homicide rate in states with the death penalty has been 48% – 101% higher than in states without the death penalty. “I think Michigan made a wise decision 150 years ago,” said the state’s governor, John Engler, a Republican, referring to the state’s abolition of the death penalty in 1846. “We’re pretty proud of the fact that we don’t have the death penalty.” (New York Times, 9/22/00)
States Without the Death Penalty Fared Better Over Past Decade – In the past ten years, the number of executions in the U.S. has increased while the murder rate has declined. Some commentators have maintained that the murder rate has dropped because of the increase in executions (see, e.g., W. Tucker, “Yes, the Death Penalty Deters,” Wall St. Journal, June 21, 2002). However, during this decade the murder rate in non-death penalty states has remained consistently lower than the rate in states with the death penalty.
When comparisons are made between states with the death penalty and states without, the majority of death penalty states show murder rates higher than non-death penalty states. The average of murder rates per 100,000 population in 1999 among death penalty states was 5.5, whereas the average of murder rates among non-death penalty states was only 3.6.
A look at neighboring death penalty and non-death penalty states show similar trends. Death penalty states usually have a higher murder rate than their neighboring non-death penalty states.