Where law meets data: a practical guide to expert coding in legal research

The rise of empirical methods has had a polarising effect on legal studies in Europe. On the one hand, quantitative empiricists have frequently dismissed traditional doctrinal scholarship as unscientific and its insights as unreliable. On the other hand, many doctrinal scholars are apprehensive about the perceived displacement of domain expertise from legal research caused by the empirical turn. To bridge the gap between the two camps and address their respective concerns, we propose a wider adoption of expert coding as a methodology for legal research. Expert coding is a method for systematic parsing and representation of phenomena such as legal principles in a structured form, using researchers' subject matter expertise. To facilitate the uptake of expert coding, we provide a step-by-step guide that addresses not only the coding process but also fundamental prerequisites such as conceptualisation, operationalisation and document selection. We argue that this methodological framework leverages legal scholars' expertise in a more impactful way than traditional doctrinal analyses. We illustrate each step and methodological principle with examples from European Union law.