Employing a descriptive-analytical methodology, this study examines criminal intervention against the unauthorized use of water and wastewater services within the legal frameworks of Iran, the United Kingdom, and the European Union, with a specific focus on the judicial practice of selected Iranian courts of first instance and appellate courts. The necessity of this research stems from the fact that water is no longer merely a privately exploitable asset, but a vital infrastructural public service, an element of public security, and a cornerstone of environmental governance; consequently, sole reliance on administrative mechanisms appears insufficient to curb network tampering and unlawful resource abstraction. The findings indicate that Iranian law, principally anchored in specific legislation such as the 2017 Act on the Punishment of Unauthorized Users of Water, Electricity, Telephone, Wastewater, and Gas, exhibits an explicit inclination toward criminalization. In contrast, English law draws a clear distinction between interference with utility infrastructure and the unlawful exploitation of natural resources, while the European Union adheres to a risk-based, harmonized, and minimalist regulatory model. Furthermore, an analysis of judicial precedents reveals that the mere report of the Iranian Water and Wastewater Company, unsupported by technical evidence, definitive identification of the actual beneficiary/perpetrator, and corroborating circumstances, is insufficient to establish criminal liability, and the presumption of innocence prevails in cases of doubt. However, where supported by empirical documentation, photographic evidence, damage assessments, and in the absence of an effective defense, both criminal and civil liability are deemed justified.