(1) This section applies only in a criminal proceeding and so applies in addition to section 108A.
(2) If the person referred to in that section is a defendant, the credibility evidence is not admissible unless the court gives leave.
(3) Despite subsection (2), leave is not required if the evidence is about whether the defendant--(a) is biased or has a motive to be untruthful, or(b) is, or was, unable to be aware of or recall matters to which his or her previous representation relates, or(c) has made a prior inconsistent statement.
(4) The prosecution must not be given leave under subsection (2) unless evidence adduced by the defendant has been admitted that--(a) tends to prove that a witness called by the prosecution has a tendency to be untruthful, and(b) is relevant solely or mainly to the witness's credibility.
(5) A reference in subsection (4) to evidence does not include a reference to evidence of conduct in relation to--(a) the events in relation to which the defendant is being prosecuted, or(b) the investigation of the offence for which the defendant is being prosecuted.
(6) Another defendant must not be given leave under subsection (2) unless the previous representation of the defendant that has been admitted includes evidence adverse to the defendant seeking leave.