The term 'CERTAIN CODE' can be broken down into three separate crossword solutions: PENAL (5 letters), AREA (4 letters), and TAXLAW (6 letters). PENAL is a term used to describe a punishment or penalty for a crime or offense. AREA is a term used to describe a particular geographical region or location. TAXLAW is a term used to describe the laws and regulations related to taxation. Together, these three terms form the phrase 'CERTAIN CODE', which could refer to a specific set of laws or regulations that must be followed in order to avoid penalties or punishments.