The moral foreign language effect (MFLE) suggests that using a second language promotes utilitarian moral decisions, though its robustness and underlying mechanisms remain debated. This study investigated the MFLE and its potential moderators, including cognitive control, emotional distress and contextual variability (operationalized as victim vulnerability through narrative cues signaling physical fragility), among 255 Chinese-English bilinguals who judged moral dilemmas in either their native or second language. Contrary to prior findings, no significant MFLE emerged, nor did cognitive control or emotional distress alone moderate moral judgments. In contrast, victim vulnerability showed a robust main effect, with higher vulnerability increasing utilitarian responses. Moreover, this effect interacted with emotional distress: it was pronounced under low distress but diminished under high distress. These findings challenge the generalizability of the MFLE and highlight the pivotal influence of emotional and contextual factors, particularly emotional arousal and perceived victim vulnerability, on moral judgments across languages.

Previous research suggests that emotion words elicit lower emotional reactivity in languages acquired later in life (LX), prompting bilinguals to make less emotional decisions when responding to emotionally charged moral dilemmas in the LX compared to their first language (L1). This study investigated the influence of word emotionality on bilinguals’ moral judgements by manipulating the degree of emotiveness of the moral questions (i.e., emotive versus neutral conditions) accompanying different types of moral dilemmas (i.e., personal/sacrificial versus impersonal/realistic). Mixed effects logistic regression models revealed that the use of the LX increased the number of utilitarian decisions in both the emotive and the neutral conditions but only in the sacrificial moral dilemmas. Moreover, the emotive questions led to more deontological moral judgements than the neutral questions but only in the L1. Taken together, these findings provide further insight into the impact of emotion on bilinguals’ moral decision-making.