Part I Fundamental rights and duties
Section II Rights, Freedoms, and Safeguards
Chapter I Personal Rights, Freedoms, and Safeguards
Article 29 Application of Criminal Law
1. No one shall be sentenced under the criminal law unless the action or omission in question is punishable under the terms of a pre-existing law, nor shall any person be the object of a security measure unless the prerequisites therefore are laid down by a pre-existing law.
2. The provisions of the previous paragraph shall not preclude the punishment up to the limits laid down by internal Portuguese law of an action or omission which was deemed criminal under the general principles of commonly recognised international law at the moment of its commission .
3. No sentence or security measure shall be applied unless it is expressly sanctioned in a pre-existing law.
4. No one shall be the object of a sentence or security measure that is more severe than those provided for at the moment of the conduct in question, or at that at which the prerequisites for the application of such a measure were fulfilled. However, criminal laws the content of which is more favourable to the defendant shall be applied retroactively .
5. No one shall be tried more than once for the same crime.
6. Citizens who are unjustly convicted shall possess the right to the review of their sentences and to compensation for such damages as they have suffered, as laid down by law .
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