Essays in Public Economics and Political Economy.

Summary This thesis is in the fields of public economics and political economy and is structured around two axes. The first and second chapters focus on redistributive policies. Specifically, they present contributions to income tax theory and adopt both a normative and a political perspective. The third and fourth chapters contribute to a better understanding of the political forces guiding reforms in multistate unions such as the European Union. They focus on the preferences of individuals who are of great importance in the decision-making process but about whom we have little direct information: politicians.My first and second chapters seek to enrich a standard model of optimal taxation, in order to better account for institutional and social contexts. Chapter 1 addresses the question of how to design a tax system when the ties between individuals are taken into account. Indeed, until now, income taxation theory has always focused on redistribution between separate individuals (or couples). But in many contexts, individuals are linked to their family, friends, village or community members, and make regular transfers to them. These transfers go from the richest to the poorest, and thus represent a form of informal redistribution. My research question is: How should the existence of these informal but redistributive transfers affect the design of taxation systems? Chapter 2 examines a salient feature of many developed countries: the large proportion of the population that does not pay income tax. Using tools from the normative tax literature that we apply to a political economy framework, we study the political economy of nonlinear tax reforms, which helps us understand why such a large share of the population is exempt from paying income tax in some countries. Although both chapters are theoretical, I use administrative and survey data to illustrate and draw concrete conclusions from my models.The last two chapters of my dissertation focus on the preferences of French and German parliamentarians on different European integration measures and are based on a first wave of questionnaire surveys conducted in 2016. In the future, we plan to continue these surveys on a regular basis in order to better understand the dynamics of the European Union and to provide an academic perspective to current EU debates with insights. The third and fourth Chapters thus explore MEPs' views on policies that, in light of the current debates and the past ten years, are of particular importance: labor market policies and European monetary union. They offer a new approach to questions of political economy by focusing on the views of a set of important actors in the decision-making process: politicians, for whom, apart from their public votes and statements, we have little direct information. In these chapters, we seek to disentangle which of the two factors is more important in the observed differences: cultural or ideological? Surprisingly, we find that for a majority of questions, the answers reflect an ideological rather than a Franco-German divide. For example, the creation of a common unemployment insurance and greater flexibility in the labor market point to a much more ideological than national divide. These results may help to highlight potential directions for European integration that could prove fruitful.