BackgroundThe present study demonstrated a causal effect of participants’ perspectives on moral decision-making by using Trolley problems and variants. Furthermore, we investigated whether empathy and borderline personality traits (BDL traits) significantly predicted participants’ choices. We used a classical Trolley problem (a causing harm scenario) and an everyday trolley-like problem (a causing inconvenience scenario). MethodsSubjects voluntarily participated in our study (N = 427, women: 54%), fulfilled BDL traits and empathy questionnaires, and randomly completed the two types of Trolley problems, presenting both three perspectives. ResultsWe provided strong evidence that participants’ perspectives on trolley problems and variants caused significant changes in their moral decision-making. Additionally, affective empathy and BDL traits significantly predicted participants’ decisions of the causing inconvenience scenario, while only BDL traits predicted choices in the causing harm scenario. ConclusionsThis study addressed several originalities by providing new experimental materials, causal results, and the significant influence of BDL traits and affective empathy on moral decision-making. These findings raised fundamental questions that are developed in the discussion.