Capital punishment does not reduce the crime rate -- it probably does reduce the murder rate, but only if it is actually applied. There is very little statistical evidence to support one view or the other, because very few jurisdictions actually impose the death penalty except in extremely rare cases. In the United States, for example, there are about 17,000 murders per year, but fewer than 50 executions. A murderer thus knows that there less than a one in 300 chance that he will be executed. The only US jurisdiction that actually imposes the death penalty on a regular basis is Texas, which carried out more than 400 executions in the period 1982-2007. There is some evidence that this has had a deterrent effect on the murder rate.
There is one aspect to the death penalty that unquestionably reduces the murder rate -- a murderer who has been executed will not commit another murder. This may seem trivial, but it is not. Convicted murderers not sentenced to death are frequently released after serving a lengthy sentence. A surprisingly high number of them kill again.
I don't think so. Homicide rates are higher in the US than in the UK - or anywhere else in the EU. And the problems and failures of the US death penalty system would very likely occur if the UK brought it back. Life without parole is much better for the worst crimes. The death penalty doesn’t prevent or reduce crime, costs a whole lot more than life in prison, and, worst of all, risks executions of innocent people.
Crime reduction (deterrence):
The death penalty doesn't keep us safer. Homicide rates for states that use the death penalty are consistently higher than for those that don’t. The most recent FBI data confirms this. For people who lack a conscience, fear of being caught is the best deterrent.
Costs, a surprise to many people:
Study after study has found that the death penalty is much more expensive than life in prison. The high costs of the death penalty are for the complicated legal process, with the largest costs at the pre-trial and trial stages. The point is to avoid executing innocent people. There are tremendous expenses in a death penalty case whether or not the defendant is convicted, let alone sentenced to death.
Who gets it:
Contrary to popular belief, the death penalty isn't reserved for the worst crimes, but for defendants with the worst lawyers. It doesn't apply to people with money. Practically everyone sentenced to death had to rely on an overworked public defender. How many people with money have been executed??
Victims:
People assume that families of murder victims want the death penalty imposed. It just isn't so. Some are against it on moral grounds. But even families who have supported the death penalty in principle have testified to the damage that the death penalty process does to families like theirs and that life without parole is an appropriate alternative.
Keeping killers off the streets for good:
Life without parole, on the books in 49 states (all except Alaska), also prevents reoffending. It means what it says, and spending the rest of your life locked up, knowing you’ll never be free, is no picnic. Two big advantages:
-an innocent person serving life can be released from prison
-life without parole costs less than the death penalty
The worst thing about the death penalty- Errors:
The system can make tragic mistakes. In 2004, Cameron Todd Willingham was executed in Texas for starting the fire that killed his children. The Texas Forensic Science Commission has determined that the arson testimony that led to his conviction was based on flawed science. As of today, 138 wrongly convicted people who were sentenced to death have been exonerated. DNA is rarely available in homicides, often irrelevant (as in the Willingham case) and can’t guarantee we won’t execute innocent people. Capital juries are dominated by people who favor the death penalty and are more likely to vote to convict.
It comes down to whether you want to bring back a system which serves only revenge amd retribution its ineffective in reducing violent crime, costs much more than alternatives and, worst of all, can lead to the nightmare of executing someone for a crime he didn’t commit.
Sources:
Death Penalty Information Center, www.deathpenaltyinfo.org,
FBI http://www.fbi.gov/ucr/ucr.htm and
http://deathpenaltyinfo.org/murder-rates-nationally-and-state#MRalpha which gives state by state rates from the FBI (alphabetically) noting which states have the death penalty
International crime rates: Cross-National Studies in Crime and Justice
http://ojp.usdoj.gov/bjs/pub/pdf/cnscj.pdf
Wikipedia International homicide rates
http://en.wikipedia.org/wiki/List_of_countries_by_homicide_rate
Ninth United Nations Survey of Crime Trends and Operations of Criminal Justice Systems
http://data360.org/pdf/20070531091045.Crime%20Trends.pdf
The Innocence Project, www.innocenceproject.org
http://deathpenaltyinfo.org/costs-death-penalty
http://www.deathpenaltyinfo.org/COcosttestimony.pdf page 3 and 4 on why the death penalty is so expensive
And, for statements of victims’ families:
www.mvfhr.org and www.mvfr.org
Article about CameronTodd Willingham: http://www.newyorker.com/reporting/2009/09/07/090907fa_fact_grann?currentPage=1