 It was then, as now, the job of the Director of Public Prosecutions to review the police dossier, to decide whether it was appropriate to prosecute and to appoint counsel to conduct the prosecution.It was also then normal for the Director to refer very serious cases to the Attorney-General or Solicitor-General, a practice that no longer exists.However, for most of the 20th century including 1957, the Director of Public Prosecutions by convention limited consideration of the guilt of the accused based on the evidence collected by the police to applying the so-called fifty percent rule, to confirm there was a reasonable chance of a conviction, and did not extend to questioning that evidence, as is the case in more recent times.