Enforcement Capture Without Enforcers:
Code Geometry and Endogenous Concentration
in an Agent-Based Model of Fundamentalism

An agent-based model with symmetric agents (N = 350; no pre-assigned enforcement roles; 3,246 runs) shows that enforcement concentration emerges endogenously from the structural geometry of codified moral systems. Five measurable institutional properties (legibility, substitutability, enforcement reward, institutional delegation, and exit cost) jointly determine which of four regimes a system enters: quiet, mixed enforcement, collapse, or capture. Institutional delegation and capital compounding reliably select a small minority into enforcement roles: the top 5 agents issue 67 to 92 percent of all punishment; endogenously appointed cadre members execute 92 to 98 percent. Two theoretically motivated retention mechanisms (sanctified suffering, membership reward) are inert across their full parameter ranges. Only degradation of the outside option converts concentration into capture: 466 of 1,080 drift-enabled runs transition to capture from conditions that otherwise yield mixed dynamics. The decisive falsifiable prediction: holding enforcement intensity constant, lowering outside-option quality increases the probability of capture. Cross-national analysis (36 countries) is consistent with this prediction: outside-option quality explains 4.4 times more variance in religious retention than enforcement intensity.