Legal scholarship in the realm of international economic law has a blind spot: the practice of international trade. Cargo and container shipping is the blood and guts of international trade, and it is fuelled by bunker oil – a hydrocarbon mixture of the dirtiest petroleum-based products. Worryingly, there is empirical evidence of bunkers being intentionally contaminated with waste oils. This fraudulent contamination violates numerous international, national, and EU rules on waste management and poses immense risks to the health of planet and people alike. These same acts of fraud are also extremely profitable, and they facilitate the smooth functioning of our global economy. The fraud is itself not just incentivised in the tight-margins reality of international trade, but it is facilitated by the lack of proper legislation and the vulnerability of the existing means of enforcement in the areas where there is legislation to comply with. Economic operators often use falsified documents to market fuel oil that should be considered as waste. Systematic wrongdoing of this kind is detrimental to the environment and risks eroding the rule of law in both its formal and substantive conceptualisations.

Private ‘bottom-up’ enforcement has been central to the efforts of the European Union (EU) to promote effective compliance with its ambitious environmental laws. This approach is strengthened by the EU's implementation of the Aarhus Convention, which aims to democratize environmental enforcement by conferring citizens and environmental non-governmental organizations (ENGOs) with legal rights of access to environmental information, rights of public participation, and rights of access to justice (the so-called ‘Aarhus mechanisms’). This article empirically assesses the extent to which the Aarhus mechanisms empower ENGOs to take an active role in the private enforcement of the EU Habitats and Birds Directives. Based on 75 surveys and 30 interviews with ENGOs from three Member States (France, Ireland, the Netherlands), we apply regulatory intermediary theory to show how European ENGOs play a vital role in intermediating between (i) EU Member States and their citizens, (ii) the EU and individual citizens, and even (iii) the EU and its Member States. We bring new empirical insights into the role of law as an enabler of regulatory intermediaries, and its potential as a tool for orchestrating regulatory intermediaries.