Rita de la Feria
@delaFeriaR
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Professor of Law, Uni Leeds | Fellow @OxfordTax | Advisory Panel @OBR_UK | Tax Law, Policy, Enforcement | New book on "Taxation and Inequalities" out Jun 2025
Lisboa | Leeds | World
Joined March 2013
Finally, big news: my paper, with the results of the Taxation and Inequalities project, is out!! Drawing upon extensive new law data, from 33 countries, and informed by a wide range of disciplines, it provides a new policy roadmap for addressing inequalities through tax systems.
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Today is an historic day for tax nerds worldwide. The Brazilian Tax Reform, which abolishes five consumption taxes, and substitutes it with one VAT was approved last night. Congratulations to all (non-tax nerd) Brazilians, who are the true winners. My full message in Portuguese:
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Com sinceras desculpas a quem já me ouviu dizer isto 300 vezes, mas: a descida do IVA nestes produtos é uma péssima idea. E não, não estou a dizer isto por causa do exemplo de Espanha, mas por causa de n exemplos, em n países, relativamente a n produtos. Porquê? Segue o 🧵.
Num debate no Parlamento, António Costa disse que o Governo vai trabalhar com o setor dos bens alimentares para encontrar formas de garantir que uma descida do IVA se reflita numa efetiva descida dos preços ao consumidor
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VAT is the 2nd most important tax in the UK, after PITs (incl NIC). Removing the exemption to private schools is a start, but tinkering at the edges is not enough. The UK needs a deep VAT reform. Urgently. My take on where we are at, and what needs to be done.
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My op-ed for the Guardian is out. Be suspicious of anyone who tells you that there is a simple tax solution to a socio-economic problem, or a simple way to boost tax revenues that includes *you* not paying.
In Britain’s trade-off laden tax system there’s no such thing as a free lunch
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A @SRanchordas e eu. Iamos tomar café hoje, mas covid. Duas mulheres portuguesas, ambas professoras catedráticas de Direito, na Holanda e em Inglaterra. Uma pós-doutorada em Yale, a outra em Oxford. Depois digam que só convidam homens porque não havia mulheres qualificadas.
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As I leave Oxford, some news to share: delighted to announce that I have been appointed to the Advisory Panel of the UK Office of Budget Responsibility (@OBR_UK). This is a big responsibility. I look forward to working with the OBR on Public Finances.
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@davidallengreen Europeans (including British) regularly underestimate what is required to travel without free movement. I recently had to delay a PhD defence because it takes the student (now a University lecturer in her country), 3 months to get a visa to come to the UK to attend it.
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Imposto único foi bem-sucedido em 169 países e só um desistiu dele, diz ‘padroeira’ do IVA @estadao:
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I have stayed out of this story, partly because I try not to comment on individual cases, but also because Dan didn’t need me to. I will say this for the record though: he may have had all this, but many in his position would have stayed quiet. @DanNeidle is just brave.
1. This was David vs Goliath, and David won!. No – Zahawi and his advisers made the tactical mistake of accidentally SLAPPing someone with plenty of financial resources, time, litigation experience, and plenty of contacts and friends in the legal, tax and media worlds.
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Together for 20 years. From young professionals to academics, from carefree to parents, from Portuguese /Irish to global hybrids. In sickness and in health. Very different personalities. Same humour, same values, same drive. To the next 20 ❤
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As it turns out this tweet was almost true. Voting now for #localelections2019 had my right to vote questioned at polling station, for being an EU citizen, even though I had polling card. Matter resolved quickly, but fairly unpleasant experience, and left me wondering for others.
That's it. Having voted for the first time in Belfast over 15 years ago, I have just voted in the UK, as a European, for the last time. Cannot help but feel sad about the symbolism of it.
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The Breast Tax: When poor women were taxed for covering their breasts, and modesty was a privilege only granted to rich women. #TaxHistory. From @mick_keen and J Slemrod's new book.
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We can - and largely should - design tax systems in a way that minimises avoidance and fraud. But no tax, no matter how well designed, is impervious to fraud. That is why, in a world full of bad tax ideas, abolishing tax administration is the stupidest one I have ever heard.
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It's out!! It took over 5 years, but we got there. I will do a proper post in time, but for now, just pure delight to see it out there. Big celebration tonight - and we can do it here, in DC.
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A good night for Europe, in France, and in Slovenia. Many dangers ahead, but 6 years ago populist movements looked unstoppable. Not today. For a united, democratic, Europe 🇪🇺.
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I have been paying taxes in the UK for 17 years. Yet, I have no voting rights, and no say on policy. I understand the reasons for citizenship-based voting. But taxation without representation is problematic in a democracy. I don't think this as tax topic gets enough attention.
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VAT is a great tax. There is no other tax that can raise as much revenue (and thus deliver public services), with such a minimal impact on the economy. Yes, it won't achieve distributional aims per se. But it will give you the revenue to achieve them.
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Growing up, one of my nicknames at home was "Mafalda", in reference to Quino's character. Because I was always asking questions, and because I was, well, difficult. I didn't like it then, but I do now. May Quino's work continue to inspire girls to never shup up.
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Law students often think the function of law school is to teach them the law. In reality, a law degree is much more about skills. It is about making students think - and feel - like lawyers. It's a subtle, but critical difference.
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Are VAT cuts the best way to help those struggling with energy bills? No. Why do we think it is? Because it's intuitive, and feels right - and because lobbying groups feed that believe.
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Two key tax policy points, where I share Dan's frustration:.(1) Number 1 rule, if you cannot define it, you cannot tax it. Disposable income, robots, etc. (2) Policy aim =/ policy instrument. Just because the aim is meritorious, does not mean the (tax) instrument is appropriate.
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9:00 desagradável troca de emails. 10:00 reunião agendada com (um) Ministro das Finanças adiada à ultima da hora. 11:00 pesquisar o significado de "nhonho" na internet. O dia promete.
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Near unanimous agreement in this great piece by @ChrisGiles_: small and big businesses, tax lawyers and consultants, tax and EU officials - and one academic. #VAT collection post Brexit, outside EEA, cannot be done with technology or paper trail only.
We need to talk about VAT, borders and Brexit. Being inside the customs union, solving regulatory alignment doesn’t solve this border problem. The choice is infrastructure, ECJ (and EU consent) or massive fraud. via @financialtimes.
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I am very grateful for the digital economy. But for everyone saying that this period shows online is the future for meetings, teaching, or conferences, I say the opposite. Online is exhausting, less effective, and, honestly, just sad. Better than nothing. That's it.
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5 reasons why rushed, ad hoc, tax policy is generally bad news:. 1. Tax policy is not always intuitive. What we think will happen is not always what does happen.
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Head of Tax at PwC Portugal (Angola and Cape Verde) has just resigned. Heads have started to roll. It is hard to overstate the impact the #LuandaLeaks is having in the Lisbon law and consultancy practice. I suspect there is more to come.
1/ PwC is shocked to discover that. it did work for a client. 2/ Governments and Portugal's central bank are looking into revelations. 3/ Eurobic held an emergency meeting and ended its relationship with dos Santos. #luandaleaks impact wrap-up, folks.
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28% of UK academic staff are non-British. Many of them face the prospect of not seeing their families for a long time. Living away is hard at any time, but much more so now. Not enough attention is being paid to this.
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Contract just signed for new book with Oxford University Press. Coming soon to a bookshop near you!*. * well, 2024.
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On #TrumpTaxReturns. Two general comments. 1) passing personal consumption off as business expenditure is tax evasion. 2) when the guiding principle of tax enforcement becomes revenue maximization, it is easier to go after those who cannot fight back.
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@JolyonMaugham Congratulations, Jolyon - and to the rest of the team. This is quite the victory.
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Dear British citizens: in non-tax, non-law, non-academic, news - after not a small amount of emotional struggle - I have applied, and been granted, settled status, i.e. indefinite leave to remain in the UK. So I guess that's it. For good or for bad, you're stuck with me.
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Booked in at (very) short-notice to give (online) training at Lviv on EU tax law. Will be part of a group of EU law academics helping Ukrainians prepare for EU accession. Both honoured and committed. We can do this 🇺🇦🇪🇺.
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On fall of the Dutch Govern. Going after low-hanging fruit, those who cannot defend themselves, is a natural response when "revenue maximization" becomes the main criteria for tax enforcement. As discussed here, this is both contra-productive and wrong:
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This may not be as sexy as big stories on low taxes paid by digital companies. But it matters. It matters for the millions of Angolans who live below the poverty line in a resource-rich country. And it should matter to all of us who care about sustainability. #LuandaLeaks.
NEW: Africa’s richest woman @isabelaangola claims to be a self-made billionaire. Today, we reveal the inside story of how she made her fortune while leaving #Angola one of the poorest countries on earth. Read #LuandaLeaks: 📹: @shirafu
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Dear all, after much consideration and soul-searching, I have concluded that exemptions and reduced rates of VAT are indeed the best way to help the poor, and quite a lot better than any direct transfers to low income households.
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Aljude Prison, where many political prisoners were held during the Portuguese Dictatorship that lasted nearly 50 years. Then, and now. For all those who sacrificed everything, and did not live long enough to see their sacrifice recognised. #25deAbrilSempre #DitaduraNuncaMais
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I know this is not a popular opinion, but. Too much attention is paid to Corporate Income Taxes policy. To the detriment of other aspects of the tax system, which could bring much bigger gains on both equity and efficiency.
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Out shopping with my mother, talking about the heroin epidemic in Portugal in 80s and 90s. 20 years since the new drug policy was implemented, and hard to even remember how bad it was. Now, almost no deaths, and associated social problems have been limited.
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My mother's message after seeing me speaking at the EU Commission's event. "I didn't really understand the content. But your necklace looks good with the black top, and you smile a lot. And that makes all the difference" . I think my mother has what it takes to be Reviewer 2 ❤️.
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It's 15 years this month since I submitted by PhD thesis. 8 since I became full Professor. I'm still often called Ms de la Feria or Mrs O'Reilly. Correspondence still comes addressed to "Dr and Mrs O'Reilly". Women's accomplishments are undermined on a regular basis. #FightBack.
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Why does everyone think VAT cuts are a good idea?! . In this paper, we consider, for the 1st time, the political economy of VAT base design, to explain positive public perceptions of VAT cuts, despite strong evidence against them. #VAT
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For those looking for African literature, I highly recommend Angolan Pepetela. One of my pandemic goals has been to read his full catalogue. Here is my latest.
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My article on Tax Fraud and Selective Law Enforcement is now available online. It identifies a global trend in tax policy and administration: the focus of anti-fraud policy is no longer combating fraud, but maximising revenue.
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One of the biggest indications about a person is how they treat staff: waiters, cleaners, security. Or in university context also, admin staff, researchers, etc. They can be very nice to me, but once you see it, it cannot be unseen.
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Consumption taxes cuts are often not fully passed on to customers. We say it, but no-one believes us because it runs counter to their priors. Then it happens, and it's a big surprise. Who knew??.
A cut in excise duty on petrol and diesel has come into effect in the Republic of Ireland but prices remain high, an industry body says.
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A maioria destes 400 milhões irá, ou nas margens (depois queixamo-nos de lucros exagerados), ou para os 20% mais ricos (que não precisam), ou ambos. A diferença que esses mesmo 400 milhões fariam se fossem só para os mais carenciados.
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New paper alert 📢. As promised, the draft of my new paper on the global minimum corporate tax rate, aka Pillar 2, is now available for free download.
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New book 🚨: in the midst of all the bad news, delighted to confirm that the book written in honour of @JudithFreedman, and edited by G Louzheniser and I, is out tomorrow. It is an outstanding collection of essays, and a fitting tribute to her work.
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My (celebration) interview to Brazilian national broadcaster, @GloboNews on the final approval of the Tax Reform law. Ironically, using a photo taken in 2018, in one of my 1st visits to campaign for the reform. What a wilde ride it has been.
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5 mitos sobre o IVA que vejo frequentemente citados no debate sobre a reforma tributária. 1. O IVA é um imposto velho. Não. Tem aprox 70 anos. Mas é tão bom que se espalhou pelo mundo inteiro em tempo record. Impostos de renda são mais antigos e ninguém discute.
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The 2022 Congress of the European Association of Tax Law Professors (EATLP) just ended, and as promised, some work news. Delighted to announce that I have been appointed general rapporteur to the 2024 Congress on the topic: "Inequalities and Taxation"
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Do you remember when tax was boring? . Your family/ friends rolled their eyes when you mentioned work, and the response you got at parties was "oh, right". Now, not a day goes by without significant tax news, and everyone has an opinion.
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Desafio ao debate aceite. Um imposto tipo CPMF é, por todas as razões referidas pelo deputado @AlexisFonteyne, uma péssima idea. Cumulativo, distorcivo, incentiva à informalidade e cria oportunidades à fraude e abuso. Já foi apelidada de "worst tax idea of 2020". E com razão.
Não gosto e não concordo com imposto cumulativos, não transparentes, distorcivos e que socializam o pagamento de impostos (CPMF, ITF, oneração da folha, etc) mas, concordo com o Paulo Guedes, não podemos interditar a discussão, isto aqui é uma democracia, por pior que seja.
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My overall take on #PandoraPapers. A lot of what is reported is, from a tax perspective - emphasis on this - legal. There are two key issues at stake in my opinion.
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Tax fraud is not a victimless crime, it's a diffuse victim crime. The perception that tax fraud as a victimless crime is basically a diffused costs problem. Harder to care and feel emphatic as regards a crime where there are no identifiable victims, rather we are all victims.
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Research news 🚨: delighted to announce that @leopoldo_parada and I are signing a contract with Oxford University Press for a new book:. "A General Theory of Anti-Avoidance of Mechanisms". In which we will discuss GAARs, SAARs, TAARs, and how everything fits together.
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🚨 New paper on VAT design now available on SSRN. 🔹️Is VAT regressive?.🔹️Do zero-rates and exemptions protect the poor?.🔹️Is the tampon tax an equality issue?. 🔹️And, critically, why do we believe the answer to all these questions is yes?.
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Son is sick, so worked all day on computer next to him, whilst he watched cartoons. Mid afternoon, son, looking at computer: "what is VAT, and why do you write about it so many times?". Is 7yo too soon?.
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Vaccination in Bahia, one of the Brazilian states most affected by the pandemic. Music and dancing. In a dark day, this made me smile. Brazilian positivity is contagious. (h/t @jcaetanoleite).
Salvador vacina mais de 50 mil em 'viradão' com filas e música Foram 28 horas ininterruptas de vacinação contra covid na capital baiana #Correio24h
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Portugal celebrates today the end of the dictatorship, and 48 years of democracy, thanks to the courage of those who fought against an oppressor that looked unbeatable. They are gone, but their memory and legacy lives on. Ao meu Avô, com infinita saudade ❤. #25deabrilsempre.
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Here is little-debated problem in tax policy. Poor public services help create vicious - as opposed to virtuous - circles. When they are bad, the willingness to pay taxes, aka tax morale, generally decreases ("why am I paying?"). When they are good, tax morale increases.
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A new cocktail is born. The caipirito: half caipirinha, half mojito. To better days, tweeps.
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In a day full of serious tax news - with arguably massive global consequences - I leave you with some light VAT relief. A slice of my birthday cake: a jaffa cake cake. Now you tell me: was it ever a biscuit??
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Just witnessed. 10 yo daughter: Avó, what is this?. My mother: it's an old phone. Daughter: how did it fit into your handbag?!
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"VAT is a regressive tax, so a temporary cut is a progressive move". I'm a great fan of @BBCNewsnight, but it would be helpful if they consulted with tax policy people before making this type of blank tax policy assertions.
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New paper challenging assumption that wealth taxation and capital income taxation are equivalent forms of taxing returns on investment. Wealth taxation is superior on increasing productivity, and reducing consumption inequality. #wealthtaxes.
Replacing capital income taxation with wealth taxation improves aggregate productivity and reduces consumption inequality, improving welfare for a large fraction of the population, from Guvenen, Kambourov, Kuruscu, Ocampo-Diaz, and Chen
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I promised myself no tax until Jan 5th, but this VAT on tampons issue cannot go unchallenged. In this paper 👇, we explain how gender equality is being instrumentalised, and public perceptions manipulated. I know this is not intuitive. But it's the truth. Just read it.
🚨 New paper on VAT design now available on SSRN. 🔹️Is VAT regressive?.🔹️Do zero-rates and exemptions protect the poor?.🔹️Is the tampon tax an equality issue?. 🔹️And, critically, why do we believe the answer to all these questions is yes?.
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My part is done. Expect the paper "Designing a Progressive VAT" to drop on the worldwide web, aka here, very soon!. Now I can just lay back, and enjoy the rest of the @OxfordTax symposium.
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Dear #taxtwitter: my draft paper on "Tax Fraud and the Rule of Law" is now out. Not finished yet, but keen on getting it out there. Comments of course welcome.
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At 4pm today. Our new paper on. "The Impact of Digitalisation on Personal Income Taxes "
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Happy New Year, tax nerds. I think it will be a particularly busy one.
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Some (nice) news to share: I will be this year's keynote speaker at the IMF/ World Bank big tax event, at the end of the Autumn Meetings with Finance Ministries. The topic of my keynote will be: 'VAT adjustments and High Inflation'.
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147 days later, I finally got to hug my mother. And dropped the kids off for the day. So this is us, enjoying the silence for the 1st time in 147 days. No homeschooling, no meals or snacks to prepare. Just the blissful sound of the sea.
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Ontem tivemos o privilégio de celebrar (aqui em Cascais) a reforma tributária do Brasil, com dois dos seus autores: um dos autores jurídicos, outro dos políticos. Que honra ter amigos assim. À reforma tributária e ao futuro do Brasil! 🥂
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Roses are red.Violets are blue.Tax policy can change the world.So keep pushing through. My (self) motivating #TaxValentine.
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Who really benefits from VAT reduced rates? Mostly, retailers. New paper, unsurprising results: "firm owners pocketed more than 55% of the VAT cut. consumers benefiting the least. employment effects were limited.". h/t @DinaPomeranz.
When consumption taxes were cut on French sit-down meals in 2009, restaurant owners kept the bulk of the windfall, say researchers at @ucsantabarbara and @USCBO. #ChartOfTheWeek
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An American, a Chilean, and a Portuguese walk into a bar. They talk about tax. The joys of the global academic community #taxlife
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Academia requires a thick skin. Peer-review is often painful, rejection is common. These are made worse by the work's nature: research takes years, and academics see it as an extension of themselves. My rule of thumb: 2/3 days mourning for rejections/bad reviews. Then move on.
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So, I had a (unexpectedly) unpleasant academic experience yesterday, and it's still playing on my mind. It was a reminder of the golden rule: be respectful, be nice, to everyone. We are entitled to our views, but not to dismiss others or their experiences.
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Over the last couple of years I have become more and more interested in the political dynamics of tax policy. I have already started working on political economy issues, and as of yesterday I have (officially) a new project with a political scientist. I am soo excited!.
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Good day @Law_Leeds, as we welcome our new PhD researcher @theoatlaw, to the Law School. Theo is a successful lawyer in Ghana, and finished the @Oxford_MScTax last year. He is now coming to work with @leopoldo_parada and I on tax incentives in African countries. Welcome, Theo!
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A universal truth of tax policy, which is often forgotten: if you cannot (legally) define it, you cannot tax (or untax) it. Inconvenient, I know, but alas, turns out knowing what "it" is, is rather important.
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Lisbon. ✅ 3 cancelled flights.✅ £400 in COVID tests.✅ hours on the phone, and an infinite amount of forms. Barely holding back the emotion. I am home. Thank you to all who kept their fingers crossed ❤
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Flying to Lisbon and arriving late. My 94 years old grandmother on the phone: what would you like for dinner? I will leave it ready in your house. Portuguese grandmothers are forces of nature.
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@IanDunt It's a well-known phenomenon in anthropology. It's about signaling belonging and commitment to the new group.
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Doing a PhD is hard. There are obvious intellectual demands. But beyond these, many outside academia don't realise how much it requires in terms of self-discipline, hard-work, and mental strength, for a prolonged period of time. It is truly a labour of love and commitment.
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🚨 As promised - *new paper*: @MaffiniG and I are delighted to announce our new policy paper on. "The Impact of Digitalisation on Personal Income Taxes". In the last years we have been concentrating on the impact of digitalisation on CIT, and to lesser extent, VAT 🧵
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No ano passado, em referência à reforma tributária no Brasil, disse em privado que,. até podemos perder, mas temos que lutar até ao fim, sem nunca vacilar, porque sistemas tributários importam. Hoje digo o mesmo, em público. Continuamos a luta por um Brasil mais justo ❤.
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Estou a sentir muito desânimo relativamente à reforma tributária no Brasil. Nem os gifs da @DuquesaDetax estão a resultar. As reformas tributárias são mesmo assim. Altos e baixos, avanços e recuos. A força da resistência é sinal que a reforma nunca esteve tão perto.
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