Estimates suggest that soft law instruments account for more than 10% of EU law, becoming more important over time. While the implementation of hard EU law has been widely studied, we know little about soft law implementation. Hard and soft law differ in the degree of obligation, precision, delegation and legitimacy – factors that can explain implementation processes and outcomes. These differences should play out in a different usage of soft law by actors in administrative and legal arenas. We expect legal actors to be comparatively skeptical in embracing EU soft law, while actors in administrations should be more open where soft law aids the implementation of hard law. We also expect different types of soft law instruments to elicit different responses. While interpretation guidelines to complicated pieces of legislation may be welcomed by administrators and judges, more open-ended programs and strategies may be ignored due to capacity limits. We test these expectations in a comparative case study on the implementation of EU soft law instruments by German administrations and courts in four policy fields: financial market regulation, competition, environmental protection and social policy. The types of soft law instruments, administrative actors and responsible courts differ substantially between these fields, allowing for a fruitful comparison while holding contextual factors constant. Overall, the paper thus provides a new angle to the diversity of implementation procedures and policy solutions in the EU multi-level system.
