This article presents part of the results from research carried out by the SPICLE team on argumentative texts written in English by student writers, both native and non-native speakers from several L1 backgrounds. The aim of the study was to compare how these writers construct stance by examining their use of devices of evidentiality, specifically, modal verbs (can, could, may, might and must) and nine reporting verbs (suggest, wonder, argue, explain, express, recognise, say, show, and state). The texts of American university writers were contrasted with those produced by five EFL groups (speakers of Spanish, Dutch, Italian, French and German). The results showed that the EFL writers either overuse or underuse modal verbs in comparison with the American writers. Regarding the use of reporting verbs, native writers use a wider range of verbs, many of which carry a higher pragmatic import for stance taking. This research is significant not only for the comparison of typological and pragmatic differences but also for the study of interlanguage features and the teaching and learning of writing conventions.