Structuring the Prison Life Index Through Value Focused Thinking Methodology

Abstract

Building a composite index (CI) is a task that requiring a series of decisions, the consequences of which will determine the scope of the tool. This is especially true for the very first steps of this construction: the definition of the theoretical framework and the selection of relevant indicators, usually referred to as the construction of the structure. However, the literature seems to focus more on the other aspects, quite often eluding those first steps or considering it a self-evident process. How to ensure the soundness of those tools when the values that they convey are not even clearly expressed? How to ensure the completeness of the structure according to the reality that it ought to synthesise when it is a highly complex or abstract one? Each of these steps involves hypotheses and presuppositions that must be explained and evaluated with care. In this article, we seek to identify a coherent method that will allow us to build the structure of CI answering those demands. The construction of a composite indicator can be conceptualised as a multi-criteria decision aiding problem (MCDA), given that it entails the aggregation of evaluations pertaining to distinct attributes. The MCDA is rich in structuring methodologies, such as Ralph Keeney's Value Focused Thinking (VFT) approach. Using a real-life application, the construction of the Prison Life Index (PLI), we try to show the relevance of those primary hypotheses by displaying the structure of the index and summarising the stage of its construction. This adapted methodology can guide index builders in the determination of a structure that comprehensively fits its intended purpose and that is not overly dependent on available data. Our article endeavours to underscore the importance of the structuring phase, arguing that it should take priority according to the ethical and moral values of the decision-maker. It should not be solely reliant on data availability, as it is the case with most composite indices. We demonstrate, through the implementation of the PLI structure developed using VFT, that it can achieve a high degree of conformity with internationally established standards pertaining to human rights. This approach not only facilitates a comprehensive understanding of the interconnections among various normative texts but also provides jurists with a visual representation of these relationships.