How does a common law judge make a decision in a case?

Answer 1

A common law judge makes decisions by applying the facts of a given case to the law as it exists under the doctrine of stare decisis, which in general terms is Latin for "let stand that which has already been decided." Under the common law, law develops from both statutes and prior case law from other courts that may have dealt with the same or similar issues. If a higher court has already established in another case that X must equal Y, then a common law judge from a lower court must also find that X equals why. Of course, judges may be persuaded by cases from other jurisdictions as well as scholarly writings, but such sources do not have the same stare decisis effect. Stare decisisis why legal precedents exist that are not easily changed outside of the legislature creating a new statute that preempts precential case or the law may be changed by a higher court deciding a lower court was wrong or a court of equal power may disagree, which can cause conflicting precedent until such time as the law evolves through statute or a clarifying decision from a higher court.

A notable distinction between common law and civil law is that civil law judges must follow statutes but are not bount by precedent from case law. While a civil law judge may be persuaded by other cases, it need not follow holdings that would otherwise be controlling to a common law judge.