T-Test for Terrorism: Did the Introduction of Proportional Representation Reduce the Terrorist Threat? A Time-Series Case Study of Algeria and Northern Ireland
Studies in Conflict & Terrorism
Can electoral reform lead to a reduction in the number of terrorist incidents? Economists have shown that the introduction of constitutional institutions such as courts in the early eighteenth century had a direct effect on investment. Could there be a similar link between the introduction of proportional representation (PR) electoral systems and a reduction in the number of terrorist attacks? Previous studies using cross-sectional data have found a negative correlation between the presence of PR-electoral systems and the number of terrorist incidents. However, earlier studies were based on aggregate figures, not on time-series data. They did not provide a direction that could be used to measure the possible effect of the introduction of PR. This research note addresses this problem. Using a paired samples t-test it is possible to show that the introduction of proportional representation in Northern Ireland and Algeria led to a marked reduction in the number of terrorist attacks. The note thus adds strength to earlier studies.

“At one time that was all we could do, that was the only avenue open to us, was to engage in armed struggle…I think it was inevitable that the nationalist people took up arms. There was no viable democratic alternative.”

—Irish Republican prisoner interviewed by Richard English

Can political participation contribute to a reduction of terrorism? In particular, can a change of the electoral system from a majoritarian system to a proportional system reduce the number of terrorist attacks? And, if so, why?

Case studies published in Studies in Conflict & Terrorism have suggested that “a considerable democratic deficit enabled a radicalization process” in the Basque Country. Consistent with this finding, increased democratic engagement can limit the prevalence of terrorist attacks. This was shown in research about Quebec also published in this journal. Here it was suggested that the risk of violent action subsided when a political party became regarded as “the legitimate … political voice and representative of Quebeckers.” And more recent cross-sectional analyses of terrorist attacks have found a strong negative correlation between having a large number of terrorist attacks and having many political parties (which ceteris paribus increases the opportunity for providing input into the political process).

This research note adds a times-series dimension to this research. After a brief overview of the literature to date, a theoretical model is presented. This argues that proportional representation (PR) increases the opportunities for voicing grievances, which in turn, provides a safety valve for democracies. To render this conclusion plausible, however, requires more than cross-sectional correlations (as in the previous literature). To show that the introduction of proportional representation has a positive effect on the reduction of terrorism a paired samples t-tests are carried out for two countries that recently have suffered a large number of terrorist attacks.