Nullum crimen sine lege

Peru

Political Constitution of Peru 1993 (2009)

TITLE I
PERSON AND SOCIETY

CHAPTER I
FUNDAMENTAL RIGHTS OF THE PERSON

Article 2

d. No one shall be prosecuted or convicted for any act or omission which was not previously prescribed in the law, expressly and unequivocally, as a punishable violation, or did not constitute an offence penalized by law.

Rome Statute

Article 22 Nullum crimen sine lege

1. A person shall not be criminally responsible under this Statute unless the conduct in question constitutes, at the time it takes place, a crime within the jurisdiction of the Court.

2. The definition of a crime shall be strictly construed and shall not be extended by analogy. In case of ambiguity, the definition shall be interpreted in favour of the person being investigated, prosecuted or convicted.

3. This article shall not affect the characterization of any conduct as criminal under international law independently of this Statute.