The above reason creates the most crucial principle of criminal law, which is: the principle of "no crime nor punishment without law."This principle asserts that people shall not be held criminally liable for his act unless the act is prescribed by law as a punishable offense at the time of the commission of such act Also. the punishments to be imposed upon the person who committed an offense shall be those prescribed by law at the time of such offense commission Thus, there is no retrospective application of criminal law.