This article analyzes the role of Mercosur's Parliament within Mercosur’s institutional design and decision-making process by associating its institutional arrangements to potential outcomes over representativeness. Generally, it discusses how representative Mercosur’s chosen mechanism for ruling seats in its Parliament, the so-called “citizen representation”, is and how that might affect coordination trends and solutions concerning political conflicts. Hence, the article investigates such mechanism in terms of its consequences for representativeness. The method relies on a Game Theoretical perspective through the application of the Banzhaf Index, which seeks to precisely measure the power of each player as their capacity to influence decisions. The article shows that, although the criteria used by the “citizen representation” is more representative than the previously used mechanism (in which all of Mercosur’s member-states had the same number of seats) in terms of the actual population within Mercosur, not all the changes brought by the mechanism are an advance when it comes to democratic participation. Brazil will be the most powerful in influencing the final decision once the mechanism is fully implemented; Argentina, in turn, will have the same amount of power in influencing the final outcome than will have Venezuela even though its population is 30% larger than the latter.

Resumo Desde sua fundação em 1991, o Mercosul tem sido caracterizado por seus mecanismos intergovernamentais e pelo processo de tomada de decisão fundado no consenso. Uma vez que esta dinâmica situa os Executivos ¬na-cionais no centro do processo de integração, levantam-se questões concernentes à representação e à legitimidade no estudo da instituição regional. Partindo do conceito de fenômenos de difusão política, o artigo aborda a busca por legitimidade por meio do mimetismo: testa-se a hipótese de que os intercâmbios plurais do Mercosul com a União Europeia criam tanto regras internas importando o modelo europeu, quanto cooperação técnica difundindo práticas institucionais. O desenho institucional influenciado por uma organização mais antiga e consolidada pode ser instrumentalizado como uma fonte de legitimidade, fomentada por funcionários do Mercosul e comunidades epistêmicas. Entretanto, essas normas regionais são diferentemente incorporadas pelos Estados-membros, motivo pelo qual, em um segundo momento, o trabalho confronta os resultados da análise da difusão institucional no Mercosul com dados sobre a efetiva internalização dessas normas, objetivando desta forma desvelar como se estabelece a ponte entre a busca por legitimidade regional e a eficácia doméstica da normativa. O resultado da análise empírica empreendida no contexto do marco teórico adotado mostra que existe um canal de transferência política entre a União Europeia e o Mercosul, atuando por meio de: (i) regras internas que importam diretamente o modelo europeu; (ii) cooperação técnica difundindo práticas institucionais; (iii) harmonização normativa de modo a favorecer in¬terações futuras.

Abstract Since its foundation in 1991, Mercosur has been characterized by intergovernmental mechanisms and a decision-making process based on consensus. This dynamic puts federal Executive branch in the center of the integration process, therefore arising questions about representation and legitimacy in the study of regional institution. Based on the concept of policy diffusion phenomena, this paper discusses the search for legitimacy through mimicry: it tests the hypothesis that plural exchanges between Mercosur and the EU yield internal rules importing European model, and stimulate technical cooperation spreading institutional practices. The institutional design influenced by a more ancient and consolidated institution can be exploited as a source of legitimacy, fostered by employees of Mercosur and epistemic communities. However, these regional standards are assimilated differently by the member states, thus, in a second moment, the work confronts the results of the analysis of institutional diffusion within with data on the effective internalization of these rules, as means to scrutinize how the regional search for legitimacy relates to the effectiveness of domestic rules. The result of the empirical analysis shows that there is a path of political transfer between the European Union and Mercosur working by: (i) internal rules which directly imports the European model; (ii) technical cooperation diffusing institutional practices; (iii) nornative harmonization as a way to favor future interactions.

Based on the discursive perspective of identity study, the article aims to demonstrate how South America's political leaders conduct the region's integration through communicative strategies focused on forging a regional identity. The article further analyzes how such constructions relate to political practices and power distribution patterns. Using qualitative and quantitative discourse analysis, the study analyzes speeches by South American heads-of-state and foreign affairs ministers in the context of institutionalization of Unasul, as well as the underlying norms in the latter's organization. The hypothesis is that the national leaders proactively promote discursive processes of social identification in the construction of Unasul as a means to legitimize and foment regional cooperation, although the identity narratives vary between countries according to their respective values.

À partir de la perspective discursive de l'étude sur les identités, on cherche ici à montrer comment la conduite de l'intégration de l'Amérique du Sud entreprise par ses leaders politiques se fait au moyen d'exercices de communication destinés à forger une identité régionale. On y examine comment ces constructions dépendent de pratiques politiques et de modèles de distribution de pouvoir. On se sert de la méthode discursive qualitative et quantitative pour examiner des discours de chefs d'État et de Ministres des Affaires Étrangères sud-américains, dans le cadre de l'institutionnalisation de l'Unasul, ainsi que les normes régissant cette organisation. On part de l'hypothèse que les leaders de chaque nation promeuvent proactivement des processus discursifs d'identification sociale dans la construction de l'Unasul, afin de légitimer et de favoriser la coopération régionale, malgré la diversité des récits identitaires entre les pays selon leurs propres valeurs.