The legality principle of crimes and punishments is derived from the Latin phrase "nullum crimen, nulla poena sine lege". Thus, no act whether immoral or against public interest or public order is considered a crime, if it is not specified by law before. As a result, the criminal judge cannot construe the individual's acts as crimes and assign punishment, even if he proves that it is worthy and useful in respect of the social interests. The second outcome is the necessity of the restrictive interpretation of the Criminal Law on the basis that the criminal judge should refer to the content of legal texts to assign the punishments and to identify the accusative titles, without resorting to analogy or adverse notion. The mentioned statements are coherent and connected phenomena in the Logic of Law. Therefore, the legality principle and its consequences are inseparable. One cannot accept a part of it and reject the rest. Even the Legislator, who provides the Criminal Law cannot deviate from this principle and its consequences, unless in exceptional cases. This is confirmed in the Islamic law, and is based on the individual's innate rights; in addition, the articles of the Constitution also approve it and make the ordinary Legislator and the Judges observe it.