Evidence-based policy making (EBPM) has been a key pillar of the better regulation agenda of the European Union. However, the extent to which it has genuinely impacted domestic policy making practices has remained largely unexplored. This study sets out to address this gap by focusing on EBPM adoption in settings with historically weak culture of technocratic rationality. To this end, the article proposes a novel analytical framework combining the concept of Europeanisation with insights from the scholarship on knowledge and evidence utilisation. The framework is then applied to the “least likely” case of Bulgaria and its National Climate and Energy Plan for 2021–2030. The article draws on 26 semi-structured interviews to analyse the use of different types of evidence in the Plan’s formulation. The study finds that genuine adoption of EBPM practices remains relatively low with evidence serving predominantly a perfunctory role. In contrast, instrumental and conceptual uses of evidence remain rare. Still, the findings point at the possibility, albeit limited, for gradual Europeanisation and uptake of evidence-based practices even in highly unfavourable conditions. This can be facilitated by a prolonged exposure to evidence-based practices, targeted EU pressure, the establishment of forums facilitating evidence exchange and the presence of “evidence-friendly” individuals within the civil service.

循证政策制定（EBPM）一直是欧盟更好监管议程的关键支柱。然而，它对国内政策制定实践的真正影响程度在很大程度上仍未得到探索。本研究旨在通过关注在历史上技术官僚理性文化薄弱的环境中采用 EBPM 来解决这一差距。为此，本文提出了一种新颖的分析框架，将欧洲化的概念与知识和证据利用方面的学术见解相结合。然后将该框架应用于保加利亚“最不可能”的案例及其 2021-2030 年国家气候和能源计划。本文利用 26 次半结构化访谈来分析该计划制定过程中不同类型证据的使用。研究发现，真正采用 EBPM 实践的人数仍然相对较低，证据主要起到了敷衍的作用。相比之下，证据的工具性和概念性用途仍然很少。尽管如此，研究结果表明，即使在非常不利的条件下，逐步欧洲化和采用循证实践的可能性虽然有限，但也是有可能的。这可以通过长期接触基于证据的实践、有针对性的欧盟压力、建立促进证据交换的论坛以及公务员队伍中“证据友好”的个人的存在来促进。