On the Disclosure of Defensive Posture: Adversarial Belief Formation and Target Selection Decisions

Due to the strategic and adaptive nature of adversaries, the deployment of new technologies is common practice in the arenas of security and defense (e.g., new baggage scanners at airports). History has shown that the deployment of these technologies has often been disclosed to the public, allowing malicious actors to potentially understand which venues are defended, and how. There is limited research examining how information disclosed about the deployment of new security measures can impact the beliefs and decisions of adversaries. Studying these beliefs and decisions is critical in obtaining insights into adversarial behavior, which can inform the allocation of defensive resources and the design of related information disclosures. This article aims to address this gap by studying how people—who are motivated to attack one among multiple targets—respond when receiving information from a defender regarding the deployment of new security measures at those targets. We address whether attackers (i) believe the information they receive from the defender and (ii) choose to attack after learning that new security measures may be deployed at their target(s) of interest. We find that attackers’ beliefs regarding where new security measures are deployed, and their decisions to attack particular targets, are impacted by the information they receive from the defender and by their understanding of the defender’s target valuations, highlighting the importance of strategic information disclosure in counterterrorism operations. In an experimental setting with two targets, when attackers ( <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline" overflow="scroll"> <mml:mi>N</mml:mi> <mml:mo>=</mml:mo> <mml:mn>975</mml:mn> </mml:math> ) knew that the defender valued one target much more than the other, they had a stronger belief that security measures would be deployed at the higher-value target, even when the defender announced that only the lower-valued target was protected with enhanced security. We also identify important factors that increase the likelihood of deterrence (i.e., when adversaries decide not to attack), which is a major goal in counterterrorism operations. Overall, this study provides novel insights into information disclosure and adversarial decision making in security and defense contexts, contributing to the operations management and behavioral decision analysis research in this domain.