This research discusses the recognition of judges' observations as valid evidence in the new Indonesian Criminal Procedure Code (New KUHAP), which will come into effect in 2026. This reform marks an important conceptual change in the Indonesian criminal evidence system. However, the regulation of judicial observation in the New KUHAP still stops at normative recognition, without any explanation of its definition, limitations, functions, or mechanisms for testing. This condition raises serious issues from the perspective of the epistemology of proof and the guarantee of a fair trial, as it opens the door to the use of subjective judicial observation that is difficult to test rationally. This research aims to analyze the position of judicial observation within the Indonesian criminal proof system, assess its implications on the standard of "legally and convincingly proven," and formulate a more measurable framework for judicial observation by learning from the experiences of the Dutch criminal procedure law. The method used was normative legal research, employing legislative, conceptual, and comparative legal approaches, supported by doctrinal and jurisprudential analysis. The research results indicate that the main issue with judicial observation lies not in its recognition as evidence but in the absence of procedural control mechanisms. This research concluded that judicial observation must be reconstructed as supplementary evidence arising from open trials, adhering to the principles of transparency, non-surprise, and equality of arms, to remain in line with a fair trial, the pursuit of material truth, and respect for human dignity.