Why are some legislators more effective than others in fragmented presidential systems? I argue that in Brazil’s fractionalized party system, legislative member organizations (LMOs) supply policy and political information that parties often lack, enabling lawmakers to advance bills. I test this claim using novel legislative effectiveness scores (LESs) for sponsors and rapporteurs in Brazil’s lower chamber. Quantitative results show that LMO affiliation is associated with higher effectiveness, but only in highly structured organizations. Public security LMOs boost both sponsorship and rapporteurship, while agribusiness LMOs increase rapporteurship effectiveness. Weakly organized LMOs show null effects. Party affiliation matters, but parties do not consistently provide information and coordination. Qualitative data identify two mechanisms by which strong LMOs operate: placing aligned members in key positions and leveraging expertise to shape agendas and voting cues. These findings recast effectiveness in Brazil as a function of cross-party informational networks rather than parties alone and identify scope conditions under which LMOs matter in other multiparty presidential democracies.

Societal “crises” are periods of turmoil and destabilization in sociocultural, political, economic, and other systems, often accompanied by violent power struggles, and sometimes significant changes in social structure. The extensive literature analyzing societal crises has concentrated on a relatively small sample of well-known cases (such as the fall of the Roman Empire), emphasizing separate aspects of these events as potential causes or consistent effects. To investigate crises in an even-handed fashion, and to avoid the potential small-sample-size bias present in several previous studies, we have created the Crisis Database (CrisisDB). CrisisDB uniformly characterizes a sample of 168 historical cases spanning millennia — from the prehistoric to the post-industrial — and varying polity complexities in diverse global regions. It features data on factors that are identified as relevant to explaining societal crises and significant “consequences” (such as warfare or epidemics), including institutional and cultural reforms (such as constitutional changes) that might occur during and immediately following the crisis period. Here, we study some examples from the CrisisDB and demonstrate our analyses, which show that the consequences of crisis experienced in each society are highly variable. The outcomes are uncorrelated with one another and, overall, the set of consequences is largely unpredictable, leading us to conclude that there is no “typical” societal crisis of the past. We offer some alternative suggestions about the forces that might propel, or mitigate, these varying consequences, highlighting areas that would benefit from future exploration, and the need for collaborative and interdisciplinary work on the study of crises.

This response memo offers a critical reassessment of the claim that ideological self-placement in Chile reflects a form of social identity. While the article under discussion provides compelling evidence of ideological stability, it risks conflating political linkage with social identity formation. In contexts of partisan decline, such as Chile’s post-authoritarian landscape, ideological categories may persist not as thick communal identities but as affective rejection fields. Drawing on insights from political psychology and Latin American party system research, this memo proposes an alternative hypothesis: ideological stability is structured by negative partisan identities—emotionally charged, ideologically coherent rejections that shape voter behavior without requiring strong organizational anchors. A stylized conceptual map illustrates the geometry of rejection in Chile’s political space. These affective coordinates help explain voter alignment in the absence of coherent in-groups or traditional parties. While preliminary, this framework underscores the importance of moving beyond ideological self-placement as a proxy for social identity and calls for renewed attention to the emotional architecture of opposition. In doing so, it invites a broader research agenda on how negative partisanship operates across fragmented democracies in Latin America.

This rebuttal responds to the argument that negative partisan identities, such as opposition to past regimes or to specific political parties, provide the primary explanation for political stability in contexts of partisan decline. While rejection dynamics do shape some voting behavior, especially in second-round contests, we contend that they cannot account for the persistence of structured electoral competition over time. Our evidence shows that many voters are defined not only by whom they reject, but also by the ideological families they belong to. We provide survey evidence demonstrating that, when ideology and negative partisanship are measured on comparable terms, the apparent advantage of the latter in explaining vote choice disappears. Recent electoral cycles further illustrate that candidates with clear ideological identities consistently capture the majority of electoral support, whereas alternatives lacking a defined ideological anchor struggle to gain traction. We conclude that ideology, understood as a social identity, is the central force generating long-term stability in electoral competition, while negative partisanship intensifies conflict in short-term, high-stakes contests.