In November 1768, he was appointed to the chair of law and economy founded expressly for him at the Palatine College of Milan. His lectures on political economy, which are based on strict utilitarian principles, are in marked accordance with the theories of the English school of economists. They are published in the collection of Italian writers on political economy ( Scrittori Classici Italiani di Economia politica , vols. xi. and xii.).  Beccaria never succeeded in producing another work to match Dei Delitti e Delle Pene , but he made various incomplete attempts in the course of his life. A short treatise on literary style was all he saw to press.
In On Crimes and Punishments Beccaria presents one of the first sustained critiques of the use of capital punishment. Briefly, his position is that capital punishment is not necessary to deter, and long term imprisonment is a more powerful deterrent since execution is transient. He starts by describing the connection between the social contract and our right to life. Locke argued that people forfeit their right to life when they initiate a state of war with other people. Beccaria disagrees. Following Hobbes, Beccaria believes that, in the social contract, we negotiate away only the minimal number of rights necessary to bring about peace. Thus, people hold onto their right to life, and do not hand this over to the public good. Given the fact that capital punishment cannot be justified by Locke's reasoning, Beccaria argues that the only other justification is that it is either necessary or useful for public good. He contests both of these claims. For Beccaria, history shows that capital punishment fails to deter determined criminals. What we know about human nature also suggests that it has minimal deterrence value. A steady example over a long period of time is more effective in creating moral habits than is a single shocking example of an execution. Beccaria argues that perpetual slavery is a more effective deterrent than capital punishment. Since we should choose the least severe punishment which accomplishes our purpose (that is, deterrence), then perpetual slavery is the preferred mode of punishment for the worst crimes. From the spectator's perspective, observing perpetual slavery will have a more lasting impression than capital punishment. Perpetual slavery will also seem more terrible from the vantage of the spectator, than from the criminal himself. Beccaria explains the psychology of the criminal who wishes to return to the state of nature in view of the gross inequity between the rich and the poor. Again, perpetual slavery is the best deterrence against this motivation. Beccaria argues further that the death penalty in fact has bad effects on society by reducing their sensitivity to human suffering. Potential criminals see it as one more method of perpetuating tyranny. Although capital punishment is practiced in most countries, it is still an error which in time will become rare. He urges rulers to adopt his stance against capital punishment, and predicts that this will give them a lasting fame as peacemakers.