A fundamental rule of evidence involves determining the admissibility of evidence by balancing the probative value of that evidence and the prejudicial effect of admitting it. In R v Swaffield the High Court addressed this fundamental issue in the context of voluntary confessions and the degree to which they are admissible in respect of voluntariness, unfairness and public policy considerations. Central to the High Court’s ruling in this case, was whether a voluntarily confessional statement — made to a person whom the confessionalist did not know was a police officer or a person acting for the police — could be admitted into evidence in a trial against the confessionalist for an offence relating to the statement. Most importantly, the High Court considered this in light of the confessionalists exercised right to silence. Toohey, Gaudron and Gummow JJ delivered a joint judgment in respect to the facts in this case holding that — following a determination that a confession was voluntary, the judge should firstly consider the discretion to reject such a confession on the grounds of unreliability before balancing this consideration on the principles of unfairness and public policy.
