Measuring extraordinary rendition and international cooperation

<jats:p> Following the launch of the War on Terror, the United States of America established a global rendition network that saw the transfer of US Central Intelligence Agency terrorist suspects to secret detention sites across the world. There has been considerable debate over how many countries participated in rendition, secret detention and interrogation during the post-9/11 period, and conventional accounts of foreign complicity suggest that diverse countries were involved, including many established democracies. However, research on rendition has continually suffered from uncertainty, a lack of data, and systematic empirical evidence due to the secret nature of counterterrorism cooperation. In this article, I argue that it is possible to study the practice of rendition, unlike many other forms of clandestine security cooperation, as it is partially observable. Specifically, suspected extraordinary rendition flight paths can be tracked using publicly available flight data. This article uses the world’s largest set of public flight data relating to rendition to estimate cross-country collaboration in rendition, secret detention and interrogation. The result suggests 307 likely rendition flights and 15 new participating countries beyond the 54 known cases, with cross validation tests demonstrating high levels of model accuracy. </jats:p>