On December 7, 2024, the Justices of the Taiwan Constitutional Court (TCC) held the TCC Annual Academic Conference of 2024 under the theme of "Principles of Constitutional Review: Retrospect and Prospect [憲法審查原則之回顧與展望]." The Annual Academic Conference, which is a long-standing yearly tradition of the TCC, aims to facilitate dialogues and exchange opinions between practitioners and academics of constitutional justice. 

    Acting President of the Judicial Yuan and Chief Justice of the TCC (ex officio), Dr. Ming-Yan SHIEH, opened the event by introducing the conference theme. He mentioned that the constitutional judiciary had cultivated various reviewing standards when adjudicating individual cases, with which the academics developed the constitutional principles employed during reviews. These principles for review were further renewed through new constitutional cases— concurrent with the change of times and social development. The conference's theme, "Principles of Constitutional Review: Retrospect and Prospect ," focused on four constitutional principles: The principle of proportionality, the equality principle, the principle of legal certainty, and the principle of lex retro non agit (non-retroactivity of the law). Through continuous practice, these principles together have constructed a framework for protecting fundamental rights and maintaining the constitutional order. In the face of new international/cross-national challenges such as climate change and AI development, the content of these principles needs to be revitalized so that the constitutionality of State conducts may be reassessed. 

    Four sessions of the conference encompassed the four aforementioned constitutional principles: 

    The first session, "The Principle of Proportionality in Retrospect and Prospect: A Review centered on J.Y. Interpretations and TCC Judgments [比例原則之回顧與展望──以大法官解釋及憲法法庭判決為中心]," was presented by Professor Hsing-An CHEN (School of Law, National Chung Hsing University). Professor CHEN's presentation analyzed the application of the principle of proportionality in constitutional cases since 2016. His presentation was joined by discussant Professor Ning-Hsiu LEE (Chinese Culture University Department of Law). Acting President SHIEH chaired this session. 

    The second session, "The Equality Principle in Retrospect and Prospect [平等原則之回顧與展望]," was presented by Professor Nai-Yi SUN (College of Law National Taiwan University). Professor SUN's presentation reviewed the equality principle's content and review standards in practice. She further examined whether the principles in practice put international human rights law into consideration. Her presentation was joined by discussant Associate Professor Chin-Wen WU (College of Law, National Chengchi University). Justice Tai-Lang LU chaired this session.  

    The third session, "The Retrospect and Prospect of the Principle of Legal Certainty in Criminal Laws in Constitutional Jurisprudence [刑罰規範之明確性審查：釋憲實務之回顧與前瞻]," was presented by Professor Chih-Jen HSUEH (College of Law National Taiwan University). Professor HSUEH's presentation revisited the application of the principle of legal certainty in criminal laws (nullum crimen, nulla poena sine lege certa) in constitutional reviews. He further proposed two reviewing criteria (regulatory density and content clarity) for future application. His presentation was joined by discussant Associate Professor Ai-Er CHEN (National Taipei University Department of Law). Justice Hui-Ching YANG chaired this session. 

    The fourth session, "Retrospect and Prospect of the Principle of Non-retroactivity of the Law—Constructing An Observation Method Based on Legal Evaluations Given to Existing Facts [法律不溯及既往原則之回顧與展望—建構既存事實已取得之法律評價之觀察方法]," was presented by Professor San-Chin LIN (School of Law, Soochow University). Professor LIN criticized the current constitutionality criteria on this issue: whether the law has a genuine retroactive effect (echte Rückwirkung). He pointed out that the criteria, combined with the indicant of "whether the existing facts concerned had already fulfilled the constituent elements of the new law when it was implemented," would neglect how the previous law would have evaluated said facts. By categorizing constitutional cases involving retroactive laws, Professor LIN proposed a new indicant for retroactive legal effects to appropriately evaluate the impact brought by new laws. Justice Tzung-Jen TSAI chaired this session.  

    Conference participants engaged productively in different aspects of each session, maintaining the tradition of facilitating dialogues between law practitioners and academics of constitutional justice and relevant fields. 

    Justice Tai-Lang LU closed the conference by summarizing the four conference sessions. He noted that the four constitutional principles discussed today were not only founded on Taiwan's socio-economical and cultural background but have also captured the essence of European and Anglo-American legal theories. Such a phenomenon is a characteristic of Taiwan's constitutional jurisprudence. He commended the fruitful exchanges during the conference, which could be further cited as important references when adjudicating future constitutional cases.