judicial precedent hierarchy

superior courts                                                                                inferior courts

supreme court                                                                                        crown court

court of appeal                                                                                      county court 

high court                                                                                       magistrates court

The hierarchy of the courts is essential in the system of judicial pecident. The superior courts bind the infereior courts and some cours are bound by their own previous descisions 

supreme court:

pre 1966 the house of lords was bound by their own descisions as seen in the london street tramways v london county coucil. if the law needed to be changed the parliament would have to pass an act of parliament as seen following the descision in DDP v smith,the law was changed for murder in the criminal justice act 1967. Since 1966 the house of lords could avoid their own descisions when the house of lords passes the practice statement 1966, which allows them to depart from a previous descision when 'it appears right to do so'. lord gardiner said '... the rigid adherence... may lead to injustice... and restict the proper development in the law.' This statement is now caled (UKSC Practice Directions 3&4) and used:

• in BRB v Herrington to overrule Addie v Dumbreck in relation of passengers being able to claim for personal injury.
• in Pepper v Hart to overrule Davis v Johnson in relation to the use of Hansard in stautory interpretation cases