Mouse-Tracking as a Window into Rule-Based Reasoning

In the domain of legal philosophy, a debate has emerged on the proper interpretation of laws, namely, whether they ought to be enforced by consulting their text or, conversely, as both their literal formulation and their underlying spirit, when judging putative transgressions. A similar controversy has translated into cognitive psychology as either focusing on the role of moral concerns or, conversely, on the primacy of text (i.e., textualism) in people’s enforcement of rules in general. Traditionally, the orthogonal manipulation of Text and Purpose of legal norms as either violated or complied with yielded two congruent conditions, with both of them transgressed or unbroken and, conversely, two incongruent ones, with only one of the two being infringed. Building on similar research, we designed a mouse-tracking experiment to uncover the spatio-temporal dynamics of text and purpose processing during judgments of rule violation. Specifically, participants’ response, speed and the trajectory of their mouse on the screen were recorded. Results replicated evidence from previous studies, namely an effect of both factors on the given response (i.e., Yes vs. No), an interference effect on RT, and generally faster conviction than acquittal. Additionally, we observed the same interference effect on both the Maximum Absolute Deviation (MAD) and Area Under the Curve (AUC) mouse-tracking indices, suggesting increased conflict for incongruent versus congruent trials. A top-down application of trajectory types suggested that the interference effect on measures of curvature may be driven primarily by discrete, rather than continuous, shifts along the response dimension that are more likely to occur during acquittal, than during conviction, decisions. Exploratory analyses employing Representational Similarity Analysis (RSA) revealed a later occurrence of the interference and a widespread processing of purpose violations. Overall, our results provide evidence of cognitive conflict during statutory interpretation, and yield novel insights into the emergence and resolution of interpretive conflict between a rule’s textual and evaluative dimensions over time.