Lawmaking under democracy is a hard business; gridlock is common and regular in even the most robustly institutionalized congresses. Producing laws is even more challenging when governing coalitions in legislatures lack a majority, as frequently occurs in multiparty democracies. Indeed, conventional wisdom expects these plurality-driven bodies to be almost continually stymied, thwarted by the opposition parties arrayed against them.

In this theoretically rich book, however, Ernesto Calvo shows that such plurality coalitions can actually achieve a surprising degree of legislative success. He draws on the example of Argentina, teasing out the logic that has allowed what he calls “plurality cartels” to push forward several significant policy initiatives. He defines these plurality cartels as parties that not only control a plurality of seats but whose “senior partners have the authority to administer the legislative gates” (p. 6). It is this latter, gatekeeping function that gives them such power, and under certain circumstances it can lead to an increase, rather than decrease, in legislative productivity.

Coupling formal modeling with an insider’s knowledge of Argentina’s formal and informal legislative practices, Calvo discerns three key “institutions that precede plenary consideration of bills” through which plurality cartels overcome the challenges they face: “committees, pre-floor party meetings, and the chamber’s directorate” (p. 9). Rather than stifling progress, each of these seeming hurdles allows for important discussion and deal making with both coalition and opposition legislators to advance the measure at hand. Intriguingly, these gatekeeping roles become all the more important when parties lose majority support in congress, as legislators change their strategy in significant ways. First, committee chairs “allow a larger set of bills to be reported from committee”; second, loss of majority support “results in an ideological drift away from the median voter of the majority party, to the benefit of legislation sponsored by the median voter of the Chamber”; and third, “more consensual amendment strategies” are undertaken (p. 13). In other words, the loss of majority support in some instances leads to less polarized outcomes than otherwise, and these may very well more closely reflect the interests of the median voter in society. Democracy thus may become more representative when a majority is lacking.

In explaining this plurality-led legislative success, Calvo makes a major contribution, helping us see beyond what he calls a “theoretical blind spot” in the literature on legislatures (p. 186). Too often, perhaps driven by an emphasis on study of the United States Congress, observers erroneously equate “cases where the president lacks a majority in congress” with “cases where the president faces an organized majority opposition” (p. 186). The reality is much more complex, especially in cross-national perspective. Legislatures in multiparty democracies are frequently not controlled by majority parties, but instead see plurality parties regularly seeking to cobble together successful coalitions. Calvo helps us see how they do that, especially in contexts where it seems most unlikely.

The evidence marshaled in Legislator Success in Fragmented Congresses in Argentina is extremely impressive. Calvo has collected data not simply on legislative outcomes, observed in roll-call votes, but on outcomes throughout the “sequential legislative process.” This allows him to detect three points of “legislative success” or failure, as proposed bills first make it out of committee, then achieve approval on the floor in their chamber of origin before gaining final approval in the alternate chamber. Such a rich understanding of the legislative process yields a data set of more than 170,000 initiatives proposed in Argentina from 1983 to 2008, of which close to a third were eventually enacted. He puts this data to outstanding use in carefully constructed tables, well-presented graphical illustrations of the major trends and findings, and clearly and persuasively constructed statistical models; together they set a high standard for thorough data collection, analysis, and hypothesis testing.

The legislative logic detailed in the book is closely derived from the Argentine case, and this is both a considerable strength and a potential weakness. By articulating the institutional house rules that govern the Argentine legislative process (much as analysts of the U.S. Congress do in their work), Calvo is able to precisely specify the strategic opportunities and choices made by the actors he studies. Both formal and informal rules stand out with bright-line clarity, and they dictate a clear logic of behavior that he models highly effectively. Yet some observers of Argentina may find it difficult to reconcile the clarity Calvo sees in legislative rules with the “institutional weakness” documented by Steven Levitsky and Victoria Murillo in their edited volume a decade ago (Argentine Democracy: The Politics of Institutional Weakness, 2005). Others may ask about the relative salience and impact of the laws under examination, as the measure of productivity seems to imply. And nonspecialists may wonder if this high degree of house-rule institutionalization—and the legislative results that flow from it—is not idiosyncratic to the Argentine case.

To answer this last criticism, Calvo fruitfully employs a study of the Uruguayan congress. Unlike the legislature of Argentina, this body exhibits “few formal rules that delegate gatekeeping authority to senior members,” and thus constitutes what Calvo terms an “open sky legislature” (p. 167). He finds that this “unregulated legislative environment” makes it harder for majority, plurality, and even minority parties to advance their legislative goals through strategic gatekeeping. Because this forces more bills into consideration on the time-consuming plenary schedule, the likelihood of legislative success is diminished, and successful laws must cater more explicitly to the median voter of the chamber (pp. 168–69). In this way, the author seems to test his argument at its two theoretical bounds of institutionalization, with Argentina representing the highly structured pole and Uruguay the largely unstructured pole. It would be clearly beyond the scope of his project for him to examine even more cases, but future work that does so will provide important robustness checks to the theory advanced in the book.

In developing the underpinnings of his argument, Calvo shows how theories developed to explain one country can be creatively applied to other countries and regions in ways that previously had not been noted. He thus builds on the literature on the U.S. legislature, elaborating on Gary Cox and Matthew McCubbins’s “procedural cartel” theory (Setting the Agenda, 2005), but extends it in an extremely novel way, highlighting how multiparty democracies may be less prone to stalemate than are systems that are dominated by two parties. In doing so, the theoretical reach of the book is truly comparative, speaking to the vast swath of countries around the world in which multiparty elections are the norm. Its arguments about the important gatekeeper roles in the legislative process are in no way confined to the region of Latin America, and indeed there is ample room for future scholarship to import Calvo’s insights to examinations of lawmaking in both developed and developing countries.

Further, the author’s findings significantly challenge existing accounts of Latin American “fragmented” congresses, which often portray legislators—especially copartisans in the majority—as completely overshadowed by the strong presidentialism that prevails in the region. Legislatures have real power, and they employ it in ways that achieve a level of consensus that the heat and smoke of political debates and journalistic accounts can obscure. In fact, Calvo shows that there is room—and a need—for new coalitions to form, negotiate, and maneuver if they are to be successful. Presidents do play a role, but somewhat counterintuitively, this role is more salient when they enjoy only plurality support in the congress than when they enjoy a majority.

Ultimately, Calvo helps us see how Argentina and the United States, two countries that resolutely see themselves as exceptional cases (and are often analyzed by academics that way), actually share a similar, cartel-driven legislative logic. In doing so, he helps us think about both countries, and about the broader cross-national experience of legislative policymaking, in a fresh and pathbreaking way.