 He began pick-pocketing with some success, eventually stealing watches and other valuables along Hounslow Road.Soon he became a highwayman and, although he was arrested several times on charges of highway robbery, six of his cases were dismissed due to lack of evidence as witnesses were unable to identify Rann.During one trial at Bow Street, while wearing an unusually large number of flowers in his coat and his irons decorated with blue ribbons, Rann reportedly addressed the presiding magistrate Sir John Fielding, saying "I know no more of the matter than you do or half as much" when he was asked if he had anything to say in his defence.