The impact of dark triad leadership on employee outcomes

Abstract

This thesis explores how managerial behaviours associated with the Dark Triad traits (narcissism, Machiavellianism, and psychopathy) affect employee outcomes in the workplace. Rather than examining broad personality traits in isolation, the study focuses on specific, observable behaviours (DTTMBs) reported by employees in publicly available workplace reviews on Glassdoor. Drawing on a dataset of coded leader behaviours and corresponding employee ratings of motivation, purpose, and direction, the research employs regression analysis done in Stata to assess the relationship between toxic leadership and these positive psychological outcomes. The findings show that trophy behaviour, risky decision-making and competitiveness, from leaders, have a significant and negative impact on employees’ sense of engagement and clarity in their roles, while others, contrary to expected, such as bullying or personal benefit-seeking, appear less consistently harmful in this sample. These results contribute to the theoretical understanding of dark leadership by illustrating how specific behavioural expressions can destabilise key drivers of employee experience and underscore the importance of moving beyond trait-level models toward more behaviourally grounded approaches.

Date of Award	7 Jul 2025
Original language	English
Awarding Institution	Universidade Católica Portuguesa
Supervisor	Jon Gruda (Supervisor)