The Devil is in the Detail: Preference Divergence and Legislative Ambiguity

Drafting guidelines and legal experts highlight that legislative texts should be written unambiguously to facilitate their interpretation and application. However, previous work on legislative complexity has largely neglected this dimension of legislative texts. We introduce new quantitative measures of syntactic ambiguity building upon drafting guidelines. We apply these measures to a new corpus of EU legislation encompassing all secondary legislation adopted in the period from 1993 until 2024. We find that preference heterogeneity of actors involved in decision-making, the involvement of the European Parliament, and directives are negatively related to syntactic ambiguity.