Chapter 4 relies on secondary sources, official documentation, and interviews to take readers further afield and explore how Lava Jato unfolded under different political conditions than in Peru, where defendants were relatively weak. Ecuador, another positive case, shows the heuristic value of the model when defendants are stronger. In particular, it further demonstrates the critical role that taskforce creation plays in engineering crusades. Mexico and Argentina are the negative cases. They both lack the type of autonomy-building reforms seen in Brazil, Peru, and Ecuador. One consequence of a deficient reform process is that investigations rarely fall in expert hands and become politicised. In particular, the Argentine case suggests that without the synergies associated with teamwork in taskforces, prosecutors are unable to investigate effectively. For this reason, the Argentine inquiry failed to gain momentum despite initially benefiting from a generous window of political opportunity.

What leads prosecutors to become crusaders in contexts where there are few precedents of Hollywood-style “prosecutor-heroes,” evidence is thin and risks high? Combining theories of the drivers of bureaucratic autonomy with analyses of crusades in Brazil and Italy, the chapter locates the origins of zealous prosecutorial role-conceptions in processes of institutional change and three “moments” (serendipity, agency, and backlash), blending structural and agentic factors. That prosecutors challenge the establishment, triggering a cascade of evidence with unorthodox tactics, is a function of institutional autonomy, criminal law reforms, and bureaucratic differentiation. Inquiries are also shaped by tactical choices, in particular, whether prosecutors form taskforces. Based on research in economics and psychology, the chapter shows that small groups are conducive to evidentiary economies of scale, legal innovation, and defensive strategies. The argument thus specifies the incentives guiding prosecutors, with attention to the organisations within which they operate. It also shows why zeal is both the engine of crusades but also the likely source of their undoing.

Crusades spur debates about what the boundaries of legal possibility ought to be when it comes to attacking corruption. They also pose the question of how much corruption we should tolerate in the name of the rule of law. While a zealous prosecutorial modus operandi is essential to dismantle criminal networks backed by state power, it can also stand in tension with due process. With this in mind, the chapter begins with a discussion of how the book’s account of the drivers of crusades contributes to debates about institution building, noting the perils of unchecked institutional (prosecutorial) strength. It also discusses the book’s contributions to the political behaviour literature, especially how attention to emotions and political cynicism offers new perspectives on the puzzle of limited electoral accountability for corruption. The chapter then explores the (de)merits of criminalisation, pointing to the importance of “norming” prosecutorial zeal in order to render prosecutions less controversial and their outcomes less precarious. It concludes with a discussion of what this “norming” exercise could look like.

Using official documents, institutional analysis, and interviews, the chapter traces Peru’s Lava Jato, the most ambitious branch of the inquiry outside Brazil. A sequence of organisational changes within the prosecution services created a more hospitable environment for proficient and innovative anti-corruption efforts. A process of bureaucratic differentiation nurtured interstices of investigative capacity, despite enduring corruption at the top of the institution. However, Lava Jato struggled to take off until all lines of inquiry were placed under the purview of a taskforce. Within case variation in this aspect of the investigative strategy shows the benefits of teamwork , as well as the role of individual personalities and professional role conceptions in determining the outcome of corruption probes. One consequence of the decision to pool investigative resources was a more aggressive and coordinated fact-finding approach. Finally, the case study shows that while prosecutorial zeal was critical for the progress of the case, it also invited backlash and risked jeopardising the legitimacy and effectiveness of the inquiry at various stages.