Essays on behavioral responses to taxation[Essais sur les réponses comportementales à l’impôt]

Debates on the desirability of higher taxes on the wealthy have recently gained significant attention. Advo-cates for more progressive tax systems argue that increasing taxation for the wealthy could both generate substantial revenues and mitigate inequalities in the face of heightened income and wealth concentration (Piketty, 2013). Conversely, opponents argue that affluent households would respond to higher taxes either by seeking ways to escape them or by reducing their efforts, investing less in the economy, which could harm the whole society. The aim of this dissertation is to bring new evidence to these debates. Overall, the revenue potential and wel-fare implications of increased taxes on the wealthy hinge on how taxpayers respond to these taxes. One key margin of response lies in taxpayers' choice of investment. Making use of the increased availability of de-tailed administrative data in several countries, the three chapters of this dissertation explore how taxpayers located at the top of the income or wealth distribution adapt their investment strategies in response to changes in the taxation environment. The first chapter studies behavioral responses to wealth taxation lever-aging administrative data for France. The second chapter, joint with Jeanne Bomare, exploits administrative data from the UK in order to analyse how tax evaders reacted to the implementation of cross-country infor-mation sharing on financial assets. The third chapter, written with Annette Alstadsaeter, Niels Johannesen and Gabriel Zucman, estimates the degree of substitution between illegal tax evasion and legal tax avoidance using Norwegian administrative data.