The European Commission for the Efficiency of Justice under the Council of Europe has adopted the first-ever European Ethical Charter on the use of artificial intelligence (AI) in judicial systems. The charter outlines a series of principles to guide public and private stakeholders in the design and deployment of AI tools and services that involve the processing of judicial decisions and data. It is also addressed to decision makers who set out the legislative and regulatory frameworks governing the development, audit or use of such tools and services. The outlined principles include respect for fundamental rights; non-discrimination; quality and security; transparency, impartiality, and fairness; and the 'under user control' principle. The document also includes a study on the use of AI in judicial systems, and an overview of uses of AI in European judicial systems that can be encouraged, that need methodological precautions, that require additional studies, and that need to be considered with extreme reservation.