On 17 April 2025, the Kosovo Specialist Chamber of the Constitutional Court (Chamber) issued a worrying judgment regarding the more lenient punishment – the lex mitior principle under Article 7 of the European Convention on Human Rights and Fundamental Freedoms (ECHR) and Article 33 of the Kosovo Constitution. The reasoning relies on the legal status of the Kosovo Specialist Chambers (KSC) and its applicable law. Hence, before embarking on the facts of the case and the analysis of the judgment, a brief overview of the KSC and applicable law is provided. The conclusions zoom out and share concerns about the wider implications of this judgment. The KSC, seated in The Hague, were established in 2015 as special judicial institutions within the justice system of Kosovo to investigate, prosecute and adjudicate international crimes committed during and in the aftermath of the conflict in Kosovo, reported in the Council of Europe Parliamentary Assembly Report Doc 12462 of 7 January 2011. As regards substantive criminal law applicable before the KSC, Article…