shall usage in legal texts is motivated by genre, not writing process

Abstract

shall is among the least common modal auxiliaries in most varieties of present-day U.S. English but is by far the most common modal in sources of law like statutes and constitutions (Brooks 2023). In this paper, we offer empirical evidence that the prominence of shall in law is motivated by genre-specific convention rather than communicative content or writing process. In a production experiment building on the findings of Martínez et al. (2024), laypeople were tasked with writing about crimes as legislators and as tour guides for foreign tourists. We find that laypeople use shall more frequently when writing in the legal genre than they do when writing about the law in non-legal settings, even when the content described is conceptually equivalent. We argue that these results offer insight into the nature of performativity and genre conventions which exist at the functional level. Marked items like deontic shall, which are relatively uncommon in non-legal genres are able to serve specialized functions in law precisely because of their markedness.