 Central to Gray 's was the system shared across the Inns of Court of progress towards a call to the Bar , which lasted approximately 12 to 14 years . A student would first study at either Oxford or Cambridge University , or at one of the Inns of Chancery , which were dedicated legal training institutions . If he studied at Oxford or Cambridge he would spend three years working towards a degree , and be admitted to one of the Inns of Court after graduation . If he studied at one of the Inns of Chancery he would do so for one year before seeking admission to the Inn of Court to which his Inn of Chancery was tied — in the case of Gray 's Inn , the attached Inns of Chancery were Staple Inn and Barnard 's Inn . 
