Unauthorised Backyard Secondary Dwelling Enforcement: When should a demolition development control order be modified to allow time for a Building Information Certificate and retrospective approval? Based on the authentic Australian judicial case Cai v Fairfield City Council [2021] NSWLEC 1657, this article disassembles the Court’s judgment process regarding evidence and law. It transforms complex judicial reasoning into clear, understandable key point analyses, helping readers identify the core of the dispute, understand the judgment logic, make more rational litigation choices, and providing case resources for practical research to readers of all backgrounds. Chapter 1: Case Overview and Core Disputes Basic Information…