Widmier, ScottGala, PrachiKoufodontis, Nikolaos IasonSerkedakis, Michael2026-04-102026-04-102025-10Widmier, S., Gala, P., Koufodontis, N.I. & Serkedakis, M. (2025), "The dark side of customer interactions: exploring the predictive power of Dark Triad traits on Jay Customer behavior in service industries". Journal of Services Marketing, Vol. 39 No. 7 pp. 772–786, doi: https://doi.org/10.1108/JSM-03-2025-0163.10.1108/JSM-03-2025-0163http://hdl.handle.net/2263/109501PURPOSE : This study aims to introduce a predictive, trait-based framework to understand Jay Customer behavior in service industries. Building on Social Exchange Theory (SET), it explores how antisocial personality traits – collectively known as the Dark Triad (Machiavellianism, Narcissism and Psychopathy) – predict deviant customer behavior and how contextual moderators shape this relationship. DESIGN/METHODOLOGY/APPROACH : A large-scale survey (n = 830) was conducted using validated scales to measure Dark Triad traits, Jay Customer behavior and situational moderators, including boredom, sensation seeking, stress and service context (business vs leisure). Hypotheses were tested using regression analysis. FINDINGS : Dark Triad traits strongly predict Jay Customer behavior across verbal, physical and financial misconduct. This relationship is significantly moderated by boredom, sensation seeking and leisure service contexts. Contrary to expectations, stress has a direct effect on misbehavior but does not moderate the trait-behavior relationship. The model explains over 63% of the variance in Jay Customer behavior. RESEARCH LIMITATIONS/IMPLICATIONS : This study advances SET by introducing the concept of conditional SET compliance, demonstrating that individuals with antisocial traits strategically violate reciprocity norms, especially under low-cost, high-stimulation conditions. It contributes a novel integration of personality psychology into the service marketing domain. PRACTICAL IMPLICATIONS : Findings offer actionable strategies for frontline service management, including personality-informed customer profiling, context-specific service design and early behavioral flagging. Recommendations are offered for employee training and policy customization in leisure versus business environments. SOCIAL IMPLICATIONS : Proactively managing disruptive behavior can reduce psychological strain on service employees and enhance service environments for all customers, contributing to improved well-being and operational sustainability. ORIGINALITY/VALUE : To the best of the authors’ knowledge, this study is the first to apply the Dark Triad framework to predict Jay Customer behavior, shifting the focus from descriptive typologies to a proactive, trait-based model. It extends SET through the concept of conditional compliance and offers practical strategies for managing customer deviance – particularly relevant in the post-pandemic service landscape.en© 2025 Emerald Publishing Limited.Customer serviceComplaintsCustomer careDysfunctional customersCustomer devianceBehavioural insightPostprint Article