Gorostiaga Marcos, NaiaraCortazar Enciondo, NereaCalvete Zumalde, Esther2026-04-132026-04-132026-03-01Gorostiaga-Marcos, N., Cortazar-Enciondo, N., & Calvete, E. (2026). The influence of hate speech on adolescents' bystander intention and TNB aggression. Journal of Research on Adolescence, 36(1). https://doi.org/10.1111/JORA.701701050-839210.1111/JORA.70170https://hdl.handle.net/20.500.14454/5624Although the visibility of trans and non-binary (TNB) individuals has increased in recent years, gender identity-based discrimination remains a significant social issue. However, there is an important gap in the research examining the mechanisms involved in TNB aggression. This study longitudinally analyzed the relationship between exposure to hate speech across different contexts and bystander intentions and aggression toward TNB individuals. Additionally, gender invariance was tested. A total of 755 adolescents aged 14 to 18 years (Mage = 16.28; SD = 0.88; 50.8% identified as girls, 48.7% as boys, and 0.3% as non-binary) completed measures assessing exposure to hate speech in several contexts, behavioral intentions when witnessing aggression, and TNB aggression at baseline. Behavioral intentions and aggression were assessed again three months later. Cross-sectional results indicated that hate speech in all contexts was associated with higher levels of aggression, with small to moderate effects. Longitudinal analyses showed that only hate speech among friends predicted aggression, with small effects. Regarding bystander intentions, none of the hate speech contexts were associated with bystander intentions either cross-sectionally or longitudinally, except for hate speech among friends, which predicted higher helping intentions with small effects. Furthermore, a bidirectional relationship was observed between bystander intentions and aggressive behaviors with small to moderate effects. Finally, the model was invariant across gender. Overall, these findings highlight the need to address adolescents' exposure to hate speech and to develop preventive strategies to reduce violence against TNB individuals, focusing on the bystander's role to promote safer and more inclusive adolescent environments.eng© 2026 The Author(s)AdolescenceAggressionBystander intentionsHate speechTrans and non-binaryjournal article2026-04-131532-7795