Bounded by culture: rationality, leadership, and the “metric vacuum” in the Brazilian justice system

While Behavioral Public Administration has extensively documented cognitive biases in Western contexts, the interplay between individual rationality and institutional culture in the Global South remains underexplored. This study investigates decision-making mechanisms among 21 senior managers within the Brazilian Justice System. Adopting a qualitative exploratory design with investigator triangulation, we mapped the cognitive and structural barriers to rationality. Contrary to the technocratic ideal, our findings reveal a ‘rationality decoupling’: while managers rhetorically value evidence-based practice, their actual decisions are dominated by status quo bias and a ‘culture of personalization.’ We identify systemic absence of formal metrics to assess decision quality, creating an accountability gap where intuition overrides data. The study concludes that ‘soft skills’ act as necessary compensatory mechanisms for structural inefficiencies. These results suggest that behavioral interventions in the justice sector must be preceded by ‘institutional boosts’ – specifically, the establishment of minimum viable decision protocols – before nudges can be effective.