The paper focuses on the budget oversight activities by the Brazilian National Congress regarding public works who show evidende of severe irregularities. It presents the main descriptive features and the most relevant hypotheses in the literature on legislative studies who might apply to legislators' ́behavior in this field. Those hypotheses are tested by means of a quantitative map to the legislative decision-making pattern in this matter (budget impoundments) during the 2002-2020 period, using as criteria for assessment the convergence with the Court of Account ́s recommendations towards each work project. It then concludes by stressing that the legislative decision-making profile shows heterogeneous patterns, which require more complex, multi-factor models to be understood, models in which different incentives affect different parliamentary groups within the corresponding decision framework.