About CenTax

Director, CenTax and Professor of Economics
University of Warwick.

Personal website

Sebastian holds an LLB in Law from Pontificia Universidad Católica and an LLM in Law from LSE. He has recently completed his PhD in tax law and policy at LSE Law School, with a focus on tax systems in developing countries. He previously worked in tax advisory at EY (UK), and in corporate M&A at Carey y Cia (Chile). His research at CenTax currently focuses on the design of tax policies affecting top earners and the wealthy.

Helen Hughson holds a BA in Economics from University of Melbourne and MSc Economics from University College London. Prior to joining the team in 2019, she spent five years working as an economist at the Reserve Bank of Australia. Her research focuses on the measurement of inequality and taxes at the top. She also leads on data infrastructure development across the team.

Andrew Lonsdale holds an MSc in Economics from the Paris School of Economics as well as degrees from LSE and McMaster University. He previously worked as an intern at the OECD’s Centre for Tax Policy and Administration. His current research at CenTax focuses on the revenue and distributional impacts of reforms to Capital Gains Tax, using administrative microdata.

Sanaya Mahajan holds a BSc in Economics from Singapore Management University (SMU) and a MSc in Economics from LSE. Her current research at the CenTax involves analysis of tax policies affecting top earners within the private equity industry, using administrative microdata. She is also assisting the development of a new dataset for analysing the firm-level impacts of personal tax policies on innovation and growth.

Camilla Skovbo Christensen holds a BSc and MSc in Economics from the University of Copenhagen, where she also recently completed her PhD. Her primary research field is public economics, and her main research topics are tax policy, savings behavior and inequality. She is a Research Officer at the International Inequalities Institute at LSE, and at the Centre for Economic Behavior and Inequality at University of Copenhagen.

David is a PhD candidate in Economics at the University of Zurich. He holds a BSc and MSc in Economics from the University of Bern. Before starting the PhD, he worked as a Research Assistant at the International Inequalities Institute at LSE. His research has been recognized by the International Institute of Public Finance with the IIPF Young Economists Award 2023. He studies issues of taxation, inequality, and pension policy, typically involving the analysis of large administrative datasets.

 Arnaud is a Postdoctoral Associate at the Massachusetts Institute of Technology (MIT), Science for Progress Initiative. He holds a BSc in Mathematics from Sorbonne Université and an MRes and a PhD in Economics from LSE. He will join HEC Paris in September 2025 as an Assistant Professor of Economics. His research focuses on growth, innovation and firm heterogeneity. His work at CenTax investigates the determinants of firm growth and the impact of migration in the UK.

César Poux is a PhD candidate in Economics at the Paris School of Economic (PSE). He holds a BSc in History and Economics from the ENS Paris-Saclay and an MSc in Economics from PSE. He previously worked as a Research Assistant at the French Council of Economic Analysis and at the International Inequalities Institute at LSE. His research focuses on the taxation of internationally mobile individuals, and transnational corporate and ownership structures.

Violetta holds a BSc in Economics in the University of Bologna and a MSc in Economics in the Paris School of Economics (PSE). She previously worked as a research intern at PSE and the OECD. Her research at CenTax focuses on real responses to taxation of high incomes, in particular effects on retirement and pension contributions, using administrative microdata and quasi-experimental methods.

Josh is responsible for supporting CenTax’s policy work. This includes working with the research team on their policy outputs, engagement with government, and managing policy events. He trained in HMRC Large Business compliance and has worked in Income Tax policy, data policy and in the Permanent Secretaries’ office. Josh holds a BA in Professional Taxation Studies from Manchester Metropolitan University and a BA in History from the University of Manchester. He is on secondment from HMRC.