The credibility rule
Under section 102 credibility evidence about a witness is not admissible. Under section 101A credibility evidence, in relation to a witness or other person, is evidence relevant to the credibility of the witness or person that is relevant only because it affects the assessment of the credibility of the witness or person, or because it affects the assessment of the credibility of the witness or person, and for some other purpose for which it is not admissible, or cannot be used, because of a provision of Parts 3.2 to 3.6.
Exceptions to the rule include:
evidence adduced in cross-examination (sections 103 and 104)
evidence in rebuttal of denials (section 106)
evidence to re-establish credibility (section 108)
evidence of persons with specialised knowledge (section 108C)
character of accused persons (section 110)
Adam v The Queen (2001) 207 CLR 96.
Facts: Constable David Carty had been drinking with some other police officers at a hotel after work. Upon leaving the hotel with Constable Auld he became involved in some sort of altercation which initially involved one other person. The altercation escalated; more young men became involved. Constable Carty suffered a fatal knife wound to the chest. Several members of the group of young men were seen to kick and stomp on him. Constable Auld tried to assist him but she was injured. At about the time of the altercation between Constable Carty and the other men, a young man named Thaier Sako suffered a knife wound to the neck. Sako had been present for some or all of the events that surrounded the death of Constable Carty. On any view, he had been present during important parts of the events and in a position where he may have been able to observe what had happened. Indeed, according to some of the evidence at trial, it was Thaier Sako who was the man who first had an altercation with Constable Carty in the car park. Initially Sako declined to be interviewed and he was charged with murder. Some six weeks later Sako indicated that he would be prepared to be interviewed. Sako was interviewed two weeks later and ultimately provided the police with two recorded interviews. The versions given by Sako supported the prosecution case. At trial the Crown desired to call Sako. By that time it was common ground that Sako would not give the version he had provided to the police in his interviews. The defence opposed the calling of the evidence.
Held: The trial judge directed a preliminary inquiry into Sako’s evidence to decide whether it was in the interests of justice to require him to give evidence in the trial. Taken as a whole, the evidence given by Sako on the voir dire was evidence that would not assist the prosecution. The trial judge permitted the Crown, pursuant to s 38 of the Evidence Act, to cross-examine him.The trial judge gave detailed reasons for allowing such cross-examination. Amongst other things, the appellant submitted that Sako’s evidence was caught by the credibility rule (s 102) unless admissible as an exception to that rule (s 103). The appellant argued that for the evidence to be excepted under s 103 it was required that the evidence be substantially probative as to the facts in issue. The evidence did not fit that category, as its only purpose was to discredit Sako.
With respect to the appellant’s argument that the credibility rule excluded the evidence, the court noted that the appellant’s argument relied upon an assertion that s 102 (“evidence that is relevant only to the witness’s credibility is not admissible”) should not be read literally. Rather the appellant said that the rule should be read as, “evidence which is not admissible on any basis other than the credibility of a witness”, should not be admitted. The court rejected this argument and found that the section should be read according to its terms. Further the court noted that this was consistent with intention of the legislation outlined in the report of the Australian Law Reform Commission. Read in that way the evidence of Sako was not caught by the credibility rule because it was relevant to issues in the trial other than merely Sako’s credibility.
Using credibility evidence
There are three ways in which credibility evidence may be used:
Attack the credibility of an opponent’s witness
Bolster the credibility of your own witness
This will particularly arise in re-examination
Attack the credibility of your own witness, e.g. if they are ‘unfavourable’
If your own witness is unfavourable credibility evidence may be used to attack their credibility in cross-examination
Attacking the credibility of an opposing witness
The credibility rule does not apply to evidence adduced in cross-examination of a witness if the evidence could substantially affect the assessment of the credibility of the witness (s103).
Here there is the attempt to prove either the witness has lied or too much time has elapsed for the witness testimony to be accurate. If the evidence could substantially effect the assessment of the credibility of the witness the rules of credibility may not apply
Attacking the credibility of a complainant of a sexual assault
Notwithstanding the exception in cross-examination of the opponents witness, if the credibility of the complainant of a sexual assault allegation is in cross-examination there is a need to consider this section. This section tries to prevents a victim of a sexual assaults credibility being attacked by being asked about their prior sexual experiences. This is regarded as a ‘rape shield law’. It aims at protecting the privacy of the victim in not having to disclose if they have a prior sexual history and the nature of that history. Prior sexual history is not relevant to the material fact in issue and usually has a low probative value
There is a need for it to show that there is a link to the material fact in issue and if there is there is a limit on the way questions are asked.
Bolstering the credibility of your own witness
If the credibility of your own witness has been attacked, there are exceptions to the rule of credibility which may enable you to bolster to credibility of your own witness in re-examination. This exception is...