Rules of evidence are a set of evidence rules that authorize how to collect, present and apply evidence for each case in courts of law.  Rules of Evidence are construed to secure fairness in administration and elimination of unjustifiable expense and delay.  In addition, the rules aim at promotion of growth and development of the law of evidence for ascertaining truth and justly determining proceedings.

Apart from the Federal Rules of Evidence, each State has its own set of rules of evidence.  Some of the examples for such rules of evidence are Alabama Rules of Evidence, Alaska Rules of Evidence and Arizona Rules of Evidence.  The rules of evidence were developed over centuries and are based upon the rules from Anglo-American common law.  The rules vary depending upon whether the venue is a criminal court, civil court or family court, and they vary by jurisdiction.

The purpose of the rules of evidence is ultimately to be fair to both parties of a case.  The rules are sometimes criticized as a legal technicality, but are an important part of the system for achieving a just result.