Data matter more than ever in the regulation of borders and migration. An apt illustration of how movement is enabled or restricted by data collection and analytics was recently reported by Eyal Weizman, founding director of the London-based research agency Forensic Architecture that specialises in the production and analysis of evidence about human rights violations by state and corporate actors. Prior to a business trip to Miami where he was supposed to open Forensic Architecture's first major exhibition in the US that, among other things, displayed investigations into a CIA drone strike in Pakistan and police killings of black US citizens, Weizmann was notified that his visa waiver request had been denied and that he would not be allowed to enter the United States.Upon further inquiry at the US embassy in London, he was informed that he had been flagged as a 'security threat' by an algorithm looking for suspicious patterns in applicants' data. While officials at the embassy could not tell Weizman what exactly had triggered the unfavourable judgement by the algorithm, they suggested that "it could be something [he] was involved in, people [he] was in contact with, places to which [he] had travelled (had [he] recently been in Syria, Iran, Iraq, Yemen, or Somalia or met their nationals?), hotels at which [he] stayed, or a certain pattern of relations among these things" (Weizman 2020, n.p.). Weizman was subsequently encouraged to provide the US Department of Homeland Security with details on individuals or connections that could point in the direction of terrorism or organised crime in order to purify himself and eventually be able to travel again. Since the digital records that had prompted the algorithm to flag Weizman as a security risk concerned personal and professional networks and connections that informed investigative work into human rights violations -including those committed by US institutions and their allies -Weizman declined to provide this information.Weizman's case forcefully illustrates how the "datafication of mobility and migration management" (Broeders and Dijstelbloem 2016) reconfigures what