Why the European Parliament litigates: explaining the politics of accountability in the EU rule of law enforcement case
研究欧洲议会为何在2021年后三次起诉欧盟委员会，其中两次涉及法治执行不力，发现诉讼在机构边缘化、政治渠道受阻和法律基础坚实三个条件同时满足时才会发生。
The European Parliament can bring actions for failure to act under Article 265 TFEU, yet it has rarely used this power to sanction the European Commission’s institutional inaction. From 2021, however, the EP has litigated against the Commission three times, two of which concerned rule of law (RoL) enforcement. Considering that Treaty violations and concerns about Commission underenforcement had not previously triggered litigation, why did EP political groups choose to sue the Commission for its failure to implement the RoL conditionality mechanism? This single-case study examines the institutional logic underpinning the EP’s decision to assess the conditions under which an unlikely oversight tool has become acceptable despite its institutional costs. Drawing on documentary evidence and interviews with EP policy-makers and officials, the study finds support for a strategic explanation rooted in institutional politics. The EP has used litigation to contest a growing perception of parliamentary marginalisation, particularly pronounced in the RoL context. The findings suggest that litigation becomes viable when three conditions concur: reputational stakes linked to institutional marginalisation, blocked political channels and a solid legal basis. The study contributes to debates on judicial politics and accountability, raising concerns about the prospects for sanctioning Treaty violations, including Commission’s RoL underenforcement.