prosecution to succeed, and there may then be an appreciable interval before the custody officer decides to charge him pursuant to paragraph 16.1. Even on the applicant's argument the immunity against questioning is overridden by the Act during this interval. Secondly, this particular immunity is much less ancient than others grouped under the rubric of the right of silence. It appears to reflect a course of practice, developed during the latter part of the 19th century, to abstain from questioning, not after charge, but after the suspect had been taken into custody; and it appears that in general any evidence obtained from such questioning was regarded as inadmissible: see Archbold's Criminal Pleading Evidence & Practice, 28th ed (1931), p 407. The practice does not, however, appear to have been universal, as witness the embarrassing conflict of judicial opinion recorded in the brief history of the Judges' Rules which forms the introduction to the 1964 revision of the rules (see Practice Note (Judges' Rules) [1964] 1 WLR 152). Moreover, although the Rules sprang from this conflict, they did not in terms go further than saying that persons in custody should not be questioned without first being cautioned. Evidently, this was insufficient to resolve the controversy, as witness the account given in 1929 in the Report of the Royal Commission on Police Powers and Procedure (1929) (Cmd 3297), paras 161 et seq. As already noticed, the debate on this issue seems to have been concentrated on the position of the person in