This study examined discourse effects on obligatory and non-obligatory control interpretations. 70 participants undertook three online forced-choice surveys, which monitored preferred interpretations in complement control, verbal-gerund-subject control, long-distance control and final temporal adjunct control. Survey 1 ascertained their baseline interpretations of the empty category in these constructions. Survey 2 cued the critical sentences used in survey 1 with a weakly established topic of discourse and survey 3 cued them with a strongly established one. Reference assignment in complement control remained consistent across all three conditions, illustrating that pragmatics does not infiltrate this structurally regulated and syntactically unambiguous construction. Changes in interpretation were found in the remaining three constructions. An accessibility-motivated scale of influence, combining three independent discourse factors (topic, linear distance and competition) is created to model reference determination in verbal-gerund-subject control and long-distance control. The results for temporal adjunct control are novel. They revealed a much stronger susceptibility to pragmatic interference than that reported in the literature yet the construction behaved differently from non-obligatory control under discourse pressure. We propose a structural account for final temporal adjunct control, which permits the evident interpretation shift, whilst still excluding arbitrary and sentence-external interpretations
