An Australian criminologist, Gordon Hawkins, the director of Sydney University's Institute of Criminology, doubts the damning validity of the "unsigned confessions" of Ryan in a television film documentary, "Beyond reasonable doubt". Although verbal confessions are not permissible in court, in the 1960s the public and therefore the jury, were much more trusting of the police. As to whether as a result an innocent man was hanged, there is at least a reasonable doubt. Following revelations of police corruption uncovered by various Australian police royal commissions. Australian police have to record or tape all interviews they carry out in connection with a crime. The police had no evidence of these unsigned verbal confessions. Ryan signed only a statement saying that he would not be giving any statements, verbal or written, to anyone except his lawyer. Hawkins questions why Ryan, a seasoned criminal, would suddenly feel the need to tell all to the police.