The term “unfavourable” does not mean adverse; it means not favourable: R v Souleyman (1996) 40 NSWLR 712 at 715; DPP v Garrett (a pseudonym) [2016] VSCA 31 at [47], [64]–[66]; Kanaan v R [2006] NSWCCA 109 at [83]; Doyle v R [2014] NSWCCA 4 at [292]. However, evidence is not unfavourable simply because it does not fit a particular case theory of the prosecution: Doyle v R at [292]. Section 38 may be used by the Crown to examine the extent of inconsistencies between experts. The provision is not limited to situations where the unfavourable evidence is unexpected. Where the views of experts differ, the extent and basis for disagreement can be tested with the Crown seeking leave to cross-examine under s 38: Gilham v R [2012] NSWCCA 131 at [405]. “Unfavourable to the party” means “unfavourable to the case which the party is seeking to advance”. The party’s case may be discerned from its opening, its pleadings and/or the evidence which the court has already heard or which is proposed to be called. If the evidence of the witness is inconsistent with, or likely to be contradictory of, that identified case, it will ordinarily satisfy the description of “unfavourable”. The inconsistency or contradiction may arise because the witness asserts a fact — or fails to assert a fact — in circumstances that render this unfavourable, even where it does not actually detract from the party’s case: DPP v Garrett at [67]–[69]; see also R v Kneebone (1999) 47 NSWLR 450 at 461–462.

The word “about” in the chapeau to s 38(1) makes it clear that leave may be granted to not only conduct cross-examination specifically directed to one of the subjects referred to in s 38(1), but also to the probability of establishing a factual state of affairs in relation to the matters contended for by the party conducting the cross-examination: Doyle v R at [293]; R v Le (2002) 54 NSWLR 474 at [67], [73].

Section 38(3) provides that the party may, with leave, question the witness about matters relevant only to the witness’s credibility. In some circumstances, a witness may be questioned about matters which are connected to matters of credibility, without a specific grant of leave under s 38(3). This includes where the questions concern the motive of the witness to lie in giving evidence or in respect of changes to the witness’ original statement: Odisho v R [2018] NSWCCA 19 at [12]; [52]–[54]; R v Le at [59], [66]–[67].

Whether a prosecutor can make a submission impugning the evidence of a prosecution witness where no application under s 38 is made depends on the basis upon which the credibility (in the sense which includes reliability) is sought to be impugned and the circumstances of the trial, including the other evidence: ZL v R [2023] NSWCCA 279 at [136], [145]; R v Walton [1999] NSWCCA 452 at [42]; R v Kennedy [2000] NSWCCA 487 at [40]. Where the attack on a witness is a significant one and involves a positive proposition of wrongdoing, it will usually be necessary for the prosecutor to seek leave to cross-examine the witness pursuant to s 38: ZL v R at [137]. However, where the evidence is challenged by the Crown because it is obviously contrary to the Crown case and the witness is clearly partisan (because of a relationship with the accused) and the attack made on the witness is merely that their evidence is incorrect or ought not to be accepted because of the relationship or motive, the prosecutor will not necessarily be obliged to seek leave before making a submission that the witness’s evidence ought not to be accepted: ZL v R at [138]; Odisho v R at [58]–[59].

It may be necessary to warn the jury under s 165 of the Act as to the potential unreliability of a prior inconsistent statement because of its hearsay nature.

Depending on the extent and nature of the cross-examination and the degree to which s 38 was used it may be necessary to give the following direction.