The value of the death penalty as a deterrent is proven effective.  According to University of Chicago’s economist Steven Levitt “For each 10 percent rise in a state's prison population, University of Chicago economist Steven Levitt estimated, robberies fall 7 percent, assault and burglary shrink 4 percent each, auto theft and larceny decline 3 percent each, rape falls 2 1/2 percent and murder drops 1 1/2 percent.
 

    About 20 years ago, studies were conducted that show that for every inmate executed, 7 lives were spared because others were deterred from committing murder.
 

Ernest van den aag, a Profesor of Jurisprudence at Fordham University said:
 

        "Even though statistical demonstrations are not conclusive, and perhaps annot be, capital punishment is likely to deter more than other punishemtns because people fear death more than anything else. They fear most death deliverately inflicted b law and scheduled by the courts. whatever people fear most is likely to deter most. Hence, the threat of the death penalty may deter some murderers who therwise might not have been deterred. And surely the death penalty is the only penalty that could deter prisoners already serving a life sentence and tempted to kill a guard, or offenders about tobe arrested and facing  life sentence. perhaps they will not be deterred. But they would certainly not be deterred by anything else. We owe all the proection we can give to law enforcers eposed to special risks."
 
 

Therfore by imposing the death penallty on serious criminal offenders the state is preventing further serious crimes from being committed. The threat of possible death for criminals acts as a way of deterring them from performing illegeal acts.

    In 1961 the United States banned the death penalty, resulting in the risk of going to prison for those who acted unlawfully. Due to the new standards of punishment for criminal behavior the crime rate drastically increased.