The question asks to identify the rules related to the legal principle 'nulla poena sine lege'. This Latin maxim translates to "no penalty without law". It is a fundamental principle in criminal law ensuring that individuals can only be punished for acts that were clearly defined as crimes by law prior to the commission of the act, and that the punishment itself is prescribed by law.

Understanding 'Nulla Poena Sine Lege'

This principle essentially means that criminal liability and punishment must be based on a pre-existing, clear, and accessible law. It acts as a safeguard against arbitrary state power and ensures legal certainty for citizens. Key aspects derived from this principle include:

• Legality (Lex Scripta): Offenses and penalties must be defined by written law.
• Certainty (Lex Certa): Laws must be clear and precise, not vague or ambiguous.
• Non-Retroactivity (Lex Praevia): Laws cannot be applied retroactively to punish acts committed before the law existed.
• Strict Construction (Lex Stricta): Penal statutes should be interpreted narrowly, resolving any ambiguities in favor of the accused.

Analysis of Options in Relation to 'Nulla Poena Sine Lege'

Let's examine how each option relates to the principle:

• A. Retroactivity of Penal Laws: The principle of 'nulla poena sine lege' fundamentally mandates non-retroactivity. It requires that a law must exist before an act is committed to impose punishment. While the principle is directly related by prohibiting retroactivity, the rule itself is the absence of retroactivity. The exclusion of this option suggests the question focuses on concepts that embody or support the principle.
• B. Strict Construction: This is directly supported by the principle's component of lex stricta. Interpreting penal laws strictly ensures that individuals are not held liable for conduct not clearly covered by the statute, thereby preventing arbitrary punishment.
• C. Certainty in Legislation: This aligns with the principle of lex certa. For the law to provide fair notice, it must be certain and clearly define prohibited conduct and penalties. This element is crucial for upholding 'nulla poena sine lege'.
• D. Accessibility of the law: This is essential for the principles of lex scripta (written law) and lex certa (certainty) to be effective. Citizens must be able to access and know the law to comply with it and be subject to its penalties. Without accessibility, the law cannot provide fair notice.
• E. Liberal Interpretation: This is contrary to the principle of strict construction (lex stricta). A liberal interpretation could broaden the scope of criminal liability beyond what was clearly intended by the legislature, potentially violating the certainty and legality aspects of 'nulla poena sine lege'.

Based on the analysis, the rules most directly related to and supported by the principle of 'nulla poena sine lege' are Strict Construction (B), Certainty in Legislation (C), and Accessibility of the law (D).