"On Crime and Punishments" by Cesare Beccaria.

Cesare Beccaria wrote is book 'On Crime and Punishments' in 1974, he believed that there was a great need for reform in the criminal justice system and he observed how few studies there were on the subject. His work I based on two key philosophical theories: social contract and utility. Social contract: Beccaria argues that punishment is justified only to defend the social contract and to ensure that everyone will be motivated to abide by it. …

…opinion on a person forfeiting his right to life when they initiate a state of war on other people. He argued that capital punishment is only justified if it suits the purpose or is useful for public good. In history, Beccaria showed how capital punishment fails to deter criminals and believed in punishment over long periods of time. His views on death penalty is that it makes society less humane and he doesn't condone it.