在大法官釋憲案件的程序中，本質上對各種聲請案件的處理當應以法條所定訴訟類型及其要件為依循，方能判斷上可否對該標的予以受理、或其審理之範圍如何。然於釋憲實務的運作中，大法官不乏有對聲請之標的及範圍為「擴張審理」者，即對原本不合於釋憲要件者加以審理。大法官就此使用的理由主要為「重要關聯性」或「實質援用」，然實務上對其內涵均未有所明確闡釋，且適用情狀亦不一致。就此即衍生諸多爭議問題，而均具有理論與實務上的重要性。本文即以大法官的「擴張審理」為研究主題，而復以實務上最常使用的「要關聯性」為主軸而開展，在歸納實務見解並精確考證此一用語於吾國學理與實務之使用情狀後，即以憲法訴訟之理論為基礎而思考論證，認為「重要關聯性」等概念並不是一個可以為「擴張審理」而演繹運用的法則，問題的核心毋寧應在於必須精確釐清各種訴訟類型中的程序要件：如以「人民聲請釋憲」而言，即係「確定終局裁判『所適用』之法令」；在「法官聲請釋憲」中即係「裁判上重要關聯性」此一要件的界定。在對此為合理說明後並思考「實質援用」的相關問題，且一併探究大法官「擴張審理」與「訴外裁判」（「聲請外解釋」）的關聯性，復就所提理論印證檢視實務上相關解釋，最後並為本文的結論與具體建議。

The procedure of judicial interpretation by the Grand Justice, in essence, should be carried out to review all kinds of cases on the types and elements of legal litigation before deciding whether to accept the claim and the scope of the petition. However, in the current practice of the Judicial Interpretation, the Grand Justice sometimes extend the judicial review beyond the claim and scope, which is against the rules of constitutional interpretation. To justify such practice, the Grand Justice has based their reasoning on the grounds of " substantially related" and "substantially cited and invoked". However, these created concepts are not explicitly interpreted and have been inconsistently applied. Therefore, many controversies in theory and practice are generated, such as the connotations of such concepts and the justification of the Grand Justice to conduct the extended judicial review. The research theme of this article is thus the "extended review" of the Grand Justice, focusing on the most commonly used justification for the practice -- "substantially related". After a thorough literature review on related theories and practice, arguments and analyses of this article are based on theories of constitutional litigation. It leads to the finding that "substantially related" and similar concepts are not appropriate criteria for conducting a " extended judicial review". Instead, The core issue shall be to accurately clarify the procedural elements of various petitions for a Judicial Interpretation. For instance, in the case of " citizens' petitions for a constitutional interpretation", it is essential to identify the involved "law and order applied by the final and binding judgment". On the other hand, the "judges' petitions for a constitutional interpretation" required for a clear definition of what is " substantially related to judgment". After elaborating the concerned issues, this article probes relevant aspects of "substantially cited and invoked" as well as examines the relevance between "extended judicial review" and "judicial interpretation beyond the contexts of petition" in the constitutional interpretation procedure. The theoretical perspectives proposed earlier are then invoked to examine the concerned Grand Justice Interpretations, followed by concluding remarks and concrete recommendations of the author