Propensity and Similar-Fact Evidence

Evidence of Discreditable Conduct and Dispositional Reasoning:

What is Propensity Evidence?

Propensity evidence or ‘discreditable conduct evidence’ is evidence that may show a person has a propensity to act in a particular way or has a particular state of mind.

The danger with propensity evidence is it can encourage juries to unfairly reason that if the accused behaved in a particular way or committed similar offences in the past, then they must be guilty of the current and similar offence.

Strict exclusionary rules apply to ensure the way an accused’s criminal record or past behaviour are not used to persuade a jury that they are guilty of a new charge.

When is Discreditable Conduct Evidence Admissible?
Section 34P of the Evidence Act 1929 (SA) regulates the admissibility of evidence showing discreditable conduct or a disposition that is to be used for propensity and similar fact purposes. In other words, evidence revealing a person’s bad character.

Section 34P provides:

(1) In the trial of a charge of an offence, evidence tending to suggest that a defendant has engaged in discreditable conduct, whether or not constituting an offence, other than conduct constituting the offence ("discreditable conduct evidence”)

(a)         Cannot be used to suggest that the defendant is more likely to have committed the offence because he or she has engaged in discreditable conduct.

(b)         Is inadmissible for that purpose ("impermissible use").

(c)         Subject to subsection (2), is inadmissible for any other purpose.

(2)         Discreditable conduct evidence may be admitted for a use (the "permissible use") other than the impermissible use if, and only if:

(a)        The judge is satisfied that the probative value of the evidence admitted for a permissible use substantially outweighs any prejudicial effect it may have on the defendant.

(b)         In the case of evidence admitted for a permissible use that relies on a particular propensity or disposition of the defendant as circumstantial evidence of a fact in issue—the evidence has strong probative value having regard to the particular issue or issues arising at trial.

(3)         In the determination of the question in subsection (2)(a), the judge must have regard to whether the permissible use is, and can be kept, sufficiently separate and distinct from the impermissible use so as to remove any appreciable risk of the evidence being used for that purpose.

(4)         Subject to subsection (5), a party seeking to adduce evidence that relies on a particular propensity or disposition of the defendant as circumstantial evidence of a fact in issue under this section must give reasonable notice in writing to each other party in the proceedings in accordance with the rules of court.

(5)         The court may, if it thinks fit, dispense with the requirement in subsection (4).

How is Section 34P Applied?
Subsection (1) provides that prima facie, all discreditable conduct evidence is inadmissible, subject to a permissible use outlined under subsection (2).

A permissible use exception under subsection (2) is granted if the Court is satisfied that the probative value of the evidence outweighs any prejudicial effect it may have on the accused.

In other words, discreditable conduct evidence is admissible if it has probative value to a specific issue rather than to general conduct.

How to Determine Permissible Uses?
The prosecution must prove that any discreditable conduct evidence they seek to rely upon falls within the meaning of a permissible use, and that such evidence relates to a specific issue .

To illustrate an example, whilst a previous conviction of an assault cannot be relied on generally to prove a new charge of assault, if there exists an important or peculiar detail from the previous assault that also appears in the present case, that evidence may be admitted to reveal a disposition that the accused behaves in a very particular way.

From the outset, look to whether the two cases share such striking similarities that the only reasonable conclusion is that the same person committed the two acts. That being said, it is not essential to the admissibility of this evidence that it exhibit ‘striking similarity’ or ‘underlying unity’, although usually the evidence will lack the requisite probative force if it does not possess such characteristics.

Recent Developments:
Recent section 34P amendments have abolished the common law tests for bad character evidence, however case law is still used to inform model cases of propensity/similar fact reasoning, and to assist litigants to identify whether section 34P applies to certain evidence.

The two main cases on propensity and similar fact evidence are Pfennig and Hoch.[2]

Pfennig (1995) 182 CLR 461

‘There is no one term which satisfactorily describes evidence which is received notwithstanding that it discloses the commission of offences other than those with which the accused is charged. It is always propensity evidence, but it may be propensity evidence which falls within the category of similar fact evidence, relationship evidence or identity evidence. These categories are not exhaustive and are not necessarily mutually exclusive. The term 'similar fact' evidence is often used in a general but inaccurate sense.’

Hoch v R (1988) 165 CLR 292
‘The basis for the admission of similar fact evidence lies in it possessing a particular probative value or cogency by reason that it reveals a pattern of activity such that, if accepted, it bears no reasonable explanation other than the inculpation of the accused person in the offence charged.’

If you require legal advice or representation, please contact us at [email protected] or on (08) 8310 0054.