This paper gives an account of the implications of the Supreme Court of Canada's case-law to section 380 of the Canadian Criminal Code defining fraud. It scrutinizes the Supreme Court's construction of some of the constitutive elements of fraud such as dishonesty and prejudice caused to the victim. The author then tries to make apparent the implicit logic followed by the Supreme Court in this matter. He asks himself which values, social models, and practices the Judges want to put forward through their policy making in regard to fraud. Finally, the author contrasts the Supreme Court's rationale with different sociological perspectives stressing current practices of economic exchange and risk-taking by economic players, particularly by contractors. Among other things, the author tries to understand, in the light of sociology, what is dishonest enrichment, what economical risks are considered tolerable and what are natural hindrances to securing economic activities.