Author(s) Cecília da Conceição de Oliveira Soares
Advisor(s) Joaquim Freitas Rocha
Year 2014

Synopsis This master thesis examines the establishment of tax liability related to Income Tax. Nowadays, it is clear that tax is levied on the fact, situation, or action that is subsumed to a legal norm in its exact terms. However, in this study we will analyse the moment that tax generating fact occurs, if it happens when income is earned by taxpayers or, on the contrary, only at the time the taxable period is closed. Although indirectly, this topic has been drawing some attention to jurisprudence and doctrine in recent years, due to the multiple and ephemeral changes in tax legislation, alleged in support of fighting the deficit and national financial imbalance. This has been happening because establishing the moment that tax liability occurs in Income Tax is extremely relevant since its disregard or ignorance can constrain several constitutional rules and principles such as the Principle of Equality on Taxation or the Principle of Legal Security. Finally, related to the establishment of the tax liability in periodical taxes, like Income Tax, it is important to clarify whether a tax legislation that come into force before the taxable period is closed can be applied on all incomes obtained by taxpayers, even those earned before the new law come into force, or this kind of legal action infringes constitutional principles.

See more here.