Character evidence is a thing. It's risky because if the defence plans to claim that the accused is of good character and hence unlikely to have committed the offence with which he's charged, the prosecution is allowed to call character evidence to the contrary. Arguably it's possible to dig up dirt on anyone. It would not be hearsay on either side. It would be testimony as to the witness's experience of the accused.
Good character evidence speaks for itself, so this only relates to bad, but you can read the finer details about both
here.
Character Evidence (Vic)
Evidence of the accused’s bad character is generally inadmissible as it is unfairly prejudicial.
There are three circumstances in which bad character can be admissible:
1. Where evidence has been adduced to establish the accused’s good character, the prosecution ... can adduce evidence to contradict this;
2. …
3. Where evidence of bad character is admissible under Part 3.7 of the Evidence Act, as evidence pertaining to the credibility of a witness.
If the prosecution
wishes to cross-examine an accused about matters arising out of character evidence, it requires the leave of the court (
Section 112, Uniform Evidence Act).
Use of bad character evidence
Bad character evidence can only be used to contradict good character evidence. It cannot be used to establish guilt. The court can limit the use of bad character evidence if it risks being unfairly prejudicial for a party or if it is likely to be misleading or confusing for the jury.
Bad character evidence cannot be used to impute that the accused has a propensity to behave in a way that makes it likely they committed the offence. In this way, bad character evidence cannot be used in the same way as good character evidence, which can be used for a sort of propensity reasoning in establishing that the accused would have been unlikely to have committed the offence.
Evidence is not inadmissible simply because it shows the bad character of the accused, if it is adduced for another purpose. Such evidence may be admitted, but the jury must be warned that it should not be used for an irrelevant or prejudicial purpose.