This study is concerned with the political economy of corruption and regulatory agencies in Nigeria. It focused on the critical assessment of the performance of the Economic and Financial Crimes Commission (EFCC) in its fight against political corruption in Nigeria since its creation. Thus, this study is guided by the following research questions (1) Has the EFCC accomplished its statutory mandate in terms of reducing the rate of political corruption in Nigeria between 2000 and 2010; (2) To what extent does dual legitimacy of criminality influence the performance of the EFCC in Nigeria. To achieve our objectives of this study, we relied on the observational technique and documentation as our method of data collection. This implied that data were generated from the secondary sources, which were analyzed with the use of qualitative descriptive analysis as well as table presentations and percentages. We adopted the theory of social production and reproduction as the viable framework of analysis that explained how the activities of the EFCC have been constrained by certain environmental conditions. We observed that the EFCC has remained a tool of social and economic domination of the ruling class over the rest of the society. The study concluded that political corruption will remain unabated in this current social structure of dependence of the EFCC on the ruling class and that EFCC has not accomplished its statutory mandate in terms of reducing the rate of corruption in Nigeria. Unless these environmental conditions change, the EFCC will not accomplish its statutory obligation. However, we recommend that there is need to review the penal codes in our constitution, which will stipulate in clear terms the procedure and punishments for all categories of corrupt practices especially within the public sector.