The Political Terror Scale (PTS): A Re-introduction and a Comparison to CIRI

Despite the frequency with which scholars have utilized the Political Terror Scale (PTS), a surprising number of questions remain regarding the origins of the scale, the coding scheme it employs, and its conceptualization of "state terror." This research note attempts to clarify these issues. We also take this opportunity to compare the PTS with the Cingranelli and Richards Human Rights Data Project (CIRI). Although the PTS and CIRI are coded from the same source material and capture the same class of human rights violations, we observe some important differences between the two that we believe may be of interest to scholars in the quantitative human rights community. First, we believe that the CIRI claims a level of precision that is not possible given the source data from which both datasets are coded. We believe that the PTS offers a transparent coding system that recognizes the inherent limitations in measuring abuses of physical integrity rights. Second, we argue that the CIRI's method of summing across abuse types leads to some inappropriate categorizations. For instance, the absence of one type of abuse prevents a state from being coded into a more repressive overall category regardless of the levels of other types of abuse. Lastly, the PTS accounts for the "range" of violence committed by the state—in short, what segments of the population are targeted. We believe that range is an important dimension to consider in measuring human rights and one to which CIRI does not attend.