More than an epistemic hedge: French je sais pas 'I don't know' as a resource for the sequential organization of turns and actions

•Grammaticization of je sais pas 'I don't know' as an interactional resource.•Syntactically and morphophonologically full forms work as epistemic disclaimers.•Reduced forms tend to be discourse marker-like: hedging, floor-holding.•Turn-initial position, in responses to questions: projecting a non-fitted response.•Turn-final position, in responses to questions: functioning as a turn-exit device.

This paper examines the interrelatedness of grammar and social interaction in relation to speakers' use of the construction je sais pas 'I don't know' in French talk-in-interaction. Based on qualitative and quantitative evidence, the study documents an interconnection between the syntactic and morphophonological properties of the construction, its epistemic meaning, its placement within turn and sequence, and its interactional functioning, specifically elaborating on its use in responses to questions. Syntactically and morphophonologically full forms tend to be used as epistemic disclaimers while reduced forms tend to be discourse marker-like. The latter occur in various sequential environments in mid-turn position, accomplishing interactional purposes such as hedging, floor-holding or indexing approximation. By contrast, in turn-initial and turn-final position, they occur predominantly in responses to questions, and are specifically implicated in the sequential organization of turns and actions: In turn-initial position, they project a non-fitted response; in turn-final position they function as turn-exit devices at a moment when a responsive action has not reached conditional relevance. Results show the grammaticization of je sais pas as an interaction-organizational device that cannot be reduced to the role of epistemic hedge or stance-marker, but is profoundly implicated in the sequential organization of turns and actions.