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Insights

Op-eds, academic commentary and tax law analysis.

Tax act's pathologies and invalidities

The nature and limits of Tax Administration actions, their defects (vices), and the legal remedies under the regime of invalidities.

Fiscal Constitution and fundamental rights

The application and defeasibility of tax laws in light of the Fiscal Constitution and the reinforced principle of fiscal legality (juridicidade fiscal).

Tax sustainability and system trust

The sustainability and legitimacy of the tax system, rebalancing the tax litigation pyramid, and the role of taxation in building robust institutions and achieving the SDGs.

Technology and the new tax administration paradigm

The transition of the Tax Administration from a collection authority to a regulatory entity, the progressive implementation of the compliance-by-design paradigm, the use of Artificial Intelligence in tax management, and the emerging challenges to taxpayers' rights.

Special Series · 7 parts

Special Series: Fifty Years of the Tax Constitution (1976–2026)

  1. P. IIntroduction and Main Phases of the First Five Decades of the 1976 Constitution
  2. P. IIPhase I (1976–1989): Constitutional Demilitarisation and the Affirmation of Democratic Self-Taxation
  3. P. IIIPhase II (1989–1997): Flexibilisation of the Economic Model and Openness of Tax Typicity
  4. P. IVPhase III (1997–2008): The Revival of the Constitutional Question, the Prohibition of Retroactive Tax Laws and the Rise of Financial Contributions
  5. P. VPhase IV (2008–2019): Crisis Taxation, Retrospectivity in Periodic Taxes and Ability to Pay
  6. P. VIPhase V (2019–2026): The Reaction Against False Interpretative Laws, Extraordinary Contributions and Regulatory De-legalisation
  7. P. VIIAssessment and Conclusions on Half a Century of Constitutional Tax Case Law
Oct 2026
Special SeriesFiscal Constitution

Fifty Years of the Tax Constitution (I): Introduction and Main Phases of the First Five Decades of the 1976 Constitution

Oct 2026
Special SeriesFiscal Constitution

Fifty Years of the Tax Constitution (II): Constitutional Demilitarisation and the Affirmation of Democratic Self-Taxation (1976–1989)

Oct 2026
Special SeriesFiscal Constitution

Fifty Years of the Tax Constitution (III): Flexibilisation of the Economic Model and Openness of Tax Typicity (1989–1997)

Oct 2026
Special SeriesFiscal Constitution

Fifty Years of the Tax Constitution (IV): The Prohibition of Retroactive Tax Laws and the Rise of Financial Contributions (1997–2008)

Oct 2026
Special SeriesFiscal Constitution

Fifty Years of the Tax Constitution (V): Crisis Taxation, Retrospectivity in Periodic Taxes and Ability to Pay (2008–2019)

Oct 2026
Special SeriesFiscal Constitution

Fifty Years of the Tax Constitution (VI): False Interpretative Laws, Extraordinary Contributions and Regulatory De-legalisation (2019–2026)

Oct 2026
Special SeriesFiscal Constitution

Fifty Years of the Tax Constitution (VII): Assessment and Conclusions on Half a Century of Constitutional Tax Case Law

May 2026
NOVA Tax LabPathologies

The Portuguese Patent Box Regime

May 2026
NOVA Tax LabFiscal Constitution

The Housing Tax Shock — framework and opportunities

Mar 2026
NOVA Tax LabPathologies

Recap on the Hot Topic of Hereditary Shares in Personal Income Tax (IRS)

Jan 2025
NOVA Tax LabFiscal Constitution

The Fall of the Banking Sector Solidarity Surcharge

Jul 2024
NOVA Tax LabSystem Trust

The Taxpayer as Addressee of Tax Laws

Jun 2024
NOVA Tax LabSystem Trust

Two Kinds of Tax Lawyers?

Jun 2024
NOVA Tax LabPathologies

Capital Gains, Land Subdivisions and the IRS Transitional Regime: Revisiting Case Law

Jan 2023
NOVA Tax LabPathologies

Hidden distributions of dividends within the scope of the general anti-avoidance rule

Abr 2019
ObservadorPathologies

The New Relationship Between Taxpayers and the Tax Authority

Mar 2019
ObservadorFiscal Constitution

Double Taxation, Finland and the Single Market

Nov 2018
ObservadorFiscal Constitution

A Call for Emigration

Out 2018
ObservadorFiscal Constitution

A Budget for the Post-Truth Era