Author Description

In the early 1970s, Canadians were debating the wisdom of doing away with the death penalty. Most research on the deterrent effects of capital punishment had failed to find any evidence that abolition of the death penalty resulted in an increase in the number of murders committed. Then in 1975, Isaac Ehrlich, an economist, published a new study that emphatically supported the deterrent effect of capital punishment. Indeed, Ehrlich argued that each execution could result "on average, in seven or eight fewer murders". These findings were quickly publicized and became part of the Canadian debate. The Department of the Solicitor General commissioned this independent review of Ehrlich's work, and the work of others employing similar techniques, to summarize and comment in a non-technical manner on the 'economics of deterrence' studies and to provide a balanced and comprehensible evaluation. The evaluation examined three aspects of the research: (1) the validity of the underlying theoretical assumptions; (2) the accuracy of the data used; and (3) the appropriateness of the statistical techniques employed. The study concluded that the behavioural theoretical shortcomings of Ehrlich's work were significant, that the data limitations alone destroyed the credibility of his results, and that while the statistical techniques used were "considerably more sophisticated and appropriate", his work "does not meet the generally accepted standards of statistical research". As a more general conclusion, the author agued that while the economic deterrence studies had indeed challenged the prevailing wisdom that punishment does not deter crime, the new data was not strong enough to support the opposite position -- that "punishment does deter crime."