Navigating complexity in plain English: A longitudinal analysis of syntactic and lexical complexity development in L2 legal writing

Since the 1960s, legal writing pedagogy in the United States has been heavily influenced by the plain English movement, which largely discourages the use of legal jargon and overly complex syntactic structures in legal documents. While these efforts to democratize legal English are laudable, it is unclear whether plain English practices can accommodate the needs of multilingual, foreign legal writers who have not yet acculturated to the U.S. legal discourse. Using mixed-effects modeling, this study tracks the development of syntactic and lexical complexity in 246 hypothetical legal essays written by 31 international Master of Laws students enrolled in a year-long legal language course. Results show that after one year of instruction, students demonstrated a significant increase in the use of nominalizations and sophisticated vocabulary. However, their sentences became notably shorter, and there was a marked decrease in the use of noun phrases with pre-modifying adjective within semesters. We discuss the intersection between plain English and academic writing practices and their impact on second language (L2) writers’ developmental trajectories. We also highlight important caveats to consider when implementing plain English pedagogy in legal language classrooms.