Essential elements of legal systems

I don't know! Where have you heard this? Or is it possible that you mean the Doctrine of Judicial Precedent?

yes sir

The Doctrine of Judicial Precedence establishes that where a decision has been made (at some time in the past ... and that 'some time' could be hundreds of years!) and today the Court is hearing a case that has similar circumstances, then the Court today has to follow the reasoning and the decision of the historic case This is not always the rule. The earlier decision must be from a Court of the same authority or higher. If the earlier case was from a Court of lower standing, then 'today's' Court need not follow the earlier decision / precedent Is that good enough to explain it to you?

structure of legal system

judges are bound to follow decisions from earlier similar cases

what is Essential elements of the legal system

The judiciary, the legislature and the secretariat Does that answer your question?