International audience ; In this article, we use a mixed theoretical framework that brings together various social approaches to language study to critically examine the sociolinguistic dynamics of interviews held as part of marriage migration investigations in Belgium. Drawing upon multisite ethnographic fieldwork, we explore the ways in which political and ideological dynamics and language practices intersect in these investigations which aim to scrutinise the matrimonial intentions of couples. First, we examine the reciprocal relationships between an asymmetric interactional configuration and processes of categorization undertaken in the interviews. Second, we link these observations to a “referentialist” ideology that positions language as a transparent vehicle of truth and underpins the investigations before exploring how this ideology contributes to shaping certain practices that render invisible both the process of co-construction of meaning in interaction and its inherent asymmetry. Following this, we argue that this “invisibilisation” potentially allows ideological and political dynamics to seep into investigation processes which are claimed to be neutral. Finally, we suggest ways in which the theoretical framework used here could be harnessed as a tool to fight against instances of injustice and discrimination potentially engendered by the sociolinguistic dynamics described, contributing to a fairer negotiation and distribution of power in this context. ; Dans cet article, nous mobilisons un outillage analytique qui rassemble plusieurs sciences sociales du langage afin de porter un regard critique sur les dynamiques sociolinguistiques des entretiens réalisés dans le cadre d’enquêtes sur les migrations par la voie du mariage en Belgique. En nous appuyant sur un travail de terrain ethnographique multi-site, nous explorons les manières dont pratiques langagières et dynamiques politiques et idéologiques s’influencent mutuellement dans ces enquêtes, lesquelles ont pour but d’établir la véracité des ...