Public policies use constructive ambiguity as a linguistic and diplomatic tool to manage the conflicting views of stakeholders and facilitate policy implementation in the presence of tensions. However, the ambiguity of policy content is a knowledge problem. It can lead to misunderstandings of its ends and means and may result in failed mitigation measures for societal crises. The Business Motivation Model (BMM) combined with the UML attribute elements can solve this problem by structurally decomposing the policy content into a BMM representation. This representation is an epistemic artefact that generates meta-knowledge about the policy by clarifying its intentions and conceptual structure, thus decreasing the likelihood of it being misunderstood. We present the case of the Aviation Chapter of the Greenhouse Gas Emissions Trading System (EU ETS), where we clarify its prescriptions for the European Commission (EC), Member States, and aircraft operators using BMM concepts and relationships as deductive coding patterns. The artefact has undergone artificial empirical evaluation by expert opinion (n = 15). Possible use scenarios were discussed with enterprise modellers, climate policy researchers, and aircraft industry experts concerned with EU ETS enforcement, implementation, and auditing. The BMM representation presented advantages over the policy’s textual form and improved the aviation industry experts’ understanding of the Chapter. Future research could look into increasing the analytical capabilities of the notation to address the needs of policy researchers working with gap analyses and co-development of policy revisions with stakeholders. Other modelling and diagramming tools should be examined to enable model durability and robustness.