Undoubtedly many other cases of mistaken conviction and execution occurred and remain undocumented. The belief that execution costs less than imprisonment is false. Abolitionists believe that the offender should be required to compensate the victim's family with the offender's own income from employment or community service. There is no doubt that someone can do more alive than dead. There is no reason for the criminal to receive any compensation for his work.
Money is of no value in jail.
One of the most well known examples of the criminal contributing to the betterment of society is the case of Leopold and Loeb. In 1924 they kidnapped and murdered a fourteen year old boy just to see what it was like. They were both spared the death penalty and sentenced to life imprisonment. Together, their accomplishments include working at hospitals, teaching illiterates to read, creating a correspondence school, making significant developments in the World War II Malaria Project and writing a grammar book. Beyond its horror and incivility, it has neither protected the innocent nor deterred the wicked.