It is not the severity of punishment but its inevitability that acts as a deterrent to any crime. We regularly read about criminals who have three or four murder cases pending against them. They roam around freely committing more crimes with impunity. This is because they know that even if they are caught, they can escape punishment by using the loopholes in the law. This is also the reason relatives of some victims kill the accused when they come out on bail.
Much has been written about the need to abolish the death penalty. It is argued that there exists no conclusive evidence of its deterrent value and that the punishment is an affront to human dignity.
If the criminal has been identified beyond doubt and shows little remorse, the benefit of withholding the ultimate punishment is debatable. What should be ensured is there is no miscarriage of justice.