A more thorough explanation:

Term: Interpretatio
Definition: Interpretatio is a term used in Roman law to describe the opinion of a legal expert who interprets the law, but does not argue in court. These experts are called jurists. Their opinions were not originally binding, but in A.D. 426, the Law of Citations made the opinions of five jurists legally binding. This means that their opinions had to be followed by judges in court. Example: If a judge is unsure about how to interpret a law, they might seek the opinion of a jurist. The jurist would provide an interpretatio, or an opinion on how the law should be interpreted. This opinion would then be considered legally binding and the judge would have to follow it. Example: The Law of Citations made the opinions of five jurists legally binding. This means that if all five jurists provided the same interpretatio on a particular law, judges would have to follow it, even if they disagreed with it. In summary, interpretatio is the opinion of a legal expert who interprets the law, and the Law of Citations made the opinions of five jurists legally binding.