Designing and implementing institutional mechanisms to control corruption are key strategies for improving the democratic quality of political systems. For this reason, not only does this issue occupy a priority position in the political agenda of a number of governmental and international organizations, but there is also a large body of specialized literature on this subject. In spite of a number of existing studies that focus on the importance of the role that institutions play in curbing corruption, the literature centered specifically on the empirical evaluation of such mechanisms in a particular country, or on the theoretical analysis of how the contribute to increase accountability of public officials, is less abundant. To address this lack, this article suggests an analytical framework based on the Principal-Agent theory, to propose systematic empirical research of institutional measures for controlling corruption. This analytical framework is based on,two criteria for classification. The first one distinguishes between ex ante and ex post measures, depending on when the specific mechanisms are enacted: before or after the delegation of authority between the Principal and the Agent has taken place. The second criterion distinguishes between a priori and a posteriori measures, depending on whether the specific mechanism is implemented before or after the act of corruption itself has occurred. Different theoretical consequences derive from each approach in terms of the projected effectiveness of the ensuing controls in reducing agency problems. Thus, the proposed framework serves to shed light on two main issues: the identification of the prevailing approach to control corruption in a specific country, and the estimation of the theoretical effectiveness of that approach. However, the most important innovation prompted by the application of this analytical framework, is that it provides for several types of comparison: between different approaches for controlling corruption in various case studies, between various areas of heightened risk for corruption within a country -such as party financing, corruption of members of parliament, ministers, etc.- and between such specific risk areas in different countries. To allow these different types of comparison, the concept of a anger zone of corruption is proposed. This concept refers to the areas and functions of the system that are vulnerable to corruption: areas of vulnerability where occurrence of corruption is likely, and conditions that are likely to promote corruption. Using this concept, it is possible to delineate the vulnerable areas in a specific system, and thereafter, to apply the proposed analytical framework in order to better describe the current approaches taken to control corruption in a given country. The necessary specific steps to identify these danger zones, as well as to empirically apply the proposed analytical framework are detailed in this par using several examples from the British system. Due to the highly developed institutional measures to circumvent corruption in place in the United Kingdom, this case effectively illustrates the utility of the proposed framework. In summary, the purpose of this document is to fulfill a deficit in the existing literature on the control of corruption, by providing a novel theoretical framework for the descriptive analysis of institutional mechanisms and their theoretical effectiveness in specific contexts and at the comparative level.
