It is a widely accepted principle of economics that if two or more adults voluntarily agree to a contract or an exchange that has no negative fall-out on others, then the government should not stop such a contract. This is often called the 'principle of free contract' (PFC). There is a body of writing in economics which upholds the PFC. Yet, this ubiquitous principle is ill-defined and full of ambiguities. For instance, since it refers to voluntary choice, its proper use presumes an understanding of what is 'voluntary' and, therefore, also, of what is coercive. What is ironic is that, while philosophers and legal scholars have debated and analyzed these concepts and the validity of the principle of free contract, there is very little discussion of these in economics, even though so much of economics is founded on this principle. This has caused a lot of policy confusion. The aim of this paper is to construct general rules for when we may violate the PFC. The argument is constructed within the Paretian framework. Hence, the violation of the PFC is not justified by appeal to deontological ethics or non-welfarist criteria. This is not an easy task since the principle of free contract is often viewed as a rule that is a derivative of the Pareto principle.
