 During the 12th and 13th centuries , law was taught in the City of London , primarily by the clergy . During the 13th century , two events happened that destroyed this form of legal education ; firstly , a decree by Henry III of England on 2 December 1234 that no institutes of legal education could exist in the City of London , and secondly a papal bull was issued in 1254 that prohibited the clergy from teaching the common law , rather than canon law . As a result , the existing system of legal education fell apart . The common lawyers migrated to the hamlet of Holborn , the nearest place to the law courts at Westminster Hall that was outside the City . 
