Vietnamese students’ perceptions of language expectations and fairness in English-medium IT classes

English-Medium Instruction (EMI) has been widely adopted in higher education in non-Anglophone contexts, but its implementation has witnessed a persistent tension between officially stated English-only expectations and bilingual classroom practices. Although previous research has noticed this policy-practice gap, how EMI students interpret bilingual practices in relation to language expectations and fairness, particularly in technically demanding disciplines, has received limited scholarly attention. This qualitative case study explores Vietnamese students’ perceptions of language expectations and fairness in bilingual EMI Information Technology (IT) classes. Data were collected through semi-structured interviews with six third-year IT undergraduates enrolled in EMI courses at a Vietnamese university. The interviews were analyzed thematically to identify patterns in students’ experiences and evaluations of language use. The findings reveal that students commonly experienced EMI IT classes as effectively bilingual, despite formal English-only expectations. Most participants agreed on the use of bilingual practices to enhance fairness by enabling students with varying English proficiency levels to access disciplinary content and demonstrate technical competence. Thus, fairness was primarily associated with content comprehension rather than English development. However, divergent perspectives also emerged, with a direct opposition to bilingual practices in EMI contexts. These contrasting views highlight the coexistence of different language ideologies among students. The study suggests that bilingual practices in EMI should operate as pedagogical strategies and moral resources through which students evaluate equity and legitimacy in the classroom. The findings also highlight the need for more obvious and context-sensitive EMI policies that acknowledge bilingual realities in higher education.