From a cross-linguistic and cross-cultural perspective, this paper reports on the findings of an exploratory study examining the features of the academic texts produced by three groups of postgraduates: native speakers of Turkish (TL1), English (EL1) and Turkish speakers of English (EL2). To this end, the study involves a microdiscourse analysis of a corpus of ninety discussion sections of dissertations to identify and classify the choices made by the authors for expressing commitment/detachment in presenting knowledge claims. The results indicated interesting similarities and differences across the groups in the ways in which writers qualified their level of commitment to a higher level and detachment from the claims in their writing. In other words, this can be described as a cline from the highest to the lowest, even intentionally withholding their commitment. By looking at the hedging and boosting devices contributing to the interactive side of academic writing, the discourse constructed by Turkish L1 writers appeared to be slightly less interpersonal but highly authoritative overall. In contrast, the results suggested that the Turkish writers of English were similar to their English L1 counterparts in terms of building a significantly more cautious strategy for presenting knowledge claims and making use of relatively fewer boosting devices when presenting their claims. It is hoped that the implications of the findings can be useful for teaching of academic writing to postgraduates within the contexts of the study.