<![CDATA[The implementation of the school zoning policy in student admissions often focuses heavily on quantitative administrative targets while overlooking underground adaptation strategies that unfold once formal rules meet local realities. This study aims to identify the forms, patterns, and mechanisms of classic negative unintended consequences generated by domicile-based zoning policy implementation at the junior high school level, using an in-depth case in Padang Panjang during the 2024/2025 academic year as the empirical anchor and extending the locus through a cross-regional documentary synthesis of zoning implementation across Sumatra, Java, Kalimantan, Sulawesi, and Nusa Tenggara. Using a qualitative case study design combined with a systematic comparative document review, this research integrates semi-structured interviews, official Department of Education documents, and registration-data analysis from Padang Panjang with published academic studies and independent-oversight reports covering more than a dozen other Indonesian regions, all interpreted through Genia Kostka's policy implementation framework, specifically its fourth quadrant of classic negative unintended consequences. The results reveal two interconnected clusters that recur, with local variation, across the reviewed regions: a socio-relational cluster comprising administrative manipulation of residency documents and informal patronage networks, and a structural-technical cluster involving digital-infrastructure and geolocation dysfunctions. Cross-regional mapping indicates that these deviation forms are not confined to a single locality but reappear across at least sixteen documented cases spanning four major islands, suggesting that they constitute a structurally recurring implementation pattern rather than a context-specific anomaly. The study concludes that unintended deviations in zoning implementation nationwide arise from the friction between formal impersonal rules and personal relational realities, requiring coordinated multi-site verification and structural equilibrium rather than isolated local patches. This study remains limited by its reliance on secondary documentary evidence for the regions beyond Padang Panjang, so future research is recommended to pursue a fully comparative multi-site primary-data design to statistically test the durability of these unintended-consequence clusters as the zoning criterion itself shifts nationally toward distance-based domicile verification]]>
