The Aarhus Convention guarantees access to information, public participation and access to justice in environmental matters. The Convention as a so-called mixed-agreement has been ratified by the EU as well as by its Member States. The Convention-related case-law of the Court of Justice of the EU (CJEU) especially relating to Slovakia (see, C-240/09 – Slovak bears, C-243/15 – Slovak deers) shows that the Court has broadened the locus standi of NGOs before national courts using them in order to facilitate the enforcement of EU law. The activism followed by the Court in these judgements could be considered as environmental-specific expression of the objective of broader law enforcement before national courts. However it depends on national courts whether this kind of CJEU judgments could acquire cross-border relevance by their application of national judges. "A mű a KÖFOP-2.1.2-VEKOP-15-2016-00001 azonosítószámú, _ „A jó kormányzást megalapozó közszolgálat-fejlesztés”_ elnevezésű kiemelt projekt keretében működtetett Ludovika Kutatócsoport keretében, a Nemzeti Közszolgálati Egyetem felkérésére készült."