In more and more criminal cases, the prosecution are relying upon what is called ‘propensity evidence’. This is evidence of other behaviour of an accused person not the subject of the charges, usually on other dates, which the accused person generally isn’t currently charged with.

For example, an accused is charged with a sexual offence relating to a child under 16. The prosecution might rely upon the accused’s prior convictions for other sexual offending years earlier.

Another example is in the case of the Claremont serial killer, where the prosecution successfully applied to adduce evidence of the accused’s possession of extreme pornography, as evidence of a propensity he had to prove he committed the murders. This was evidence of other behaviour not the subject of the murder charges on the indictment.

A further example is a case involving a charge of murder, where the prosecution were permitted to lead evidence of a book the accused had written about a male serial killer.

The evidence doesn’t always have to be of uncharged acts. Sometimes, in a case involving multiple complainants and multiple charges, the prosecution might argue there should be a joint trial of each of the charges because each of the charges are propensity evidence for the other charges. So propensity evidence can consist of evidence in support of other charges you face, or matters for which there are no charges.

What are the rules for admissibility of propensity evidence?

The evidence must be ‘propensity evidence’

In order to be admissible, the evidence must actually be ‘propensity evidence’. The prosecution can’t just lead evidence of any behaviour by an accused at any time. Propensity evidence is:

• similar fact evidence;
• evidence of the conduct of the accused person;
• relationship evidence, meaning the accused’s attitude or conduct towards another person or person(s) over a period of time;
• evidence of the character or reputation of the accused; &
• evidence of a tendency the accused has or had.

As is apparent, the definition of ‘propensity evidence’ is incredibly wide and can encompass all sorts of behaviour of an accused person. It extends beyond behaviour to evidence of the accused’s attitude, character and reputation.

An example of similar fact evidence is where identity is disputed in a case, evidence of similar behaviour on other occasions might be led to establish the accused committed the offence. For example, evidence of a unique manner of walking might make it more likely the accused was the offender.

A tendency might be a sexual interest in children, or a tendency to act violently.

Relationship evidence is often evidence of previous domestic violence incidents involving the same partner, or other partners but in similar situations to the one presently charged.

If the evidence is ‘propensity evidence’, there are two main rules to determine if the court will admit it into evidence.

Significant probative value

Firstly, the evidence must have ‘significant probative value’, either by itself or having regard to other evidence adduced or to be adduced. This means the evidence is significantly probative of a fact in issue. The evidence must have more than mere relevance.

An example is in a drug dealing case, evidence of a prior drug dealing conviction would generally be significantly probative of a tendency to possess and/or sell or supply drugs. So prior drug convictions are generally significantly probative of new drug charges.

‘Fair-minded person’ test

Secondly, if the evidence has significant probative value, the court must be satisfied that:

• ‘the probative value of the evidence compared to the degree of risk of an unfair trial, is such that fair-minded people would think that the public interest in adducing all relevant evidence of guilt must have priority over the risk of an unfair trial.’

This is a balancing exercise. The court must weigh up the strength of the evidence against the risk of an unfair trial. The risk is that the jury will assume, because of the propensity evidence, that you have committed the offence. Or they might be so shocked by the other evidence that they can’t bring an impartial mind to their role as jurors.

In practice, propensity evidence that has significant probative value is almost always admitted. It is rare that evidence will be excluded on the basis that it fails this test. There are many Court of Appeal judgments to the effect that a direction from the trial Judge can ordinarily overcome the risk of an unfair trial. Many accused persons disagree with this legal principle in practice. Accused persons often feel they will not receive a fair trial if propensity evidence is admitted against them, and question whether to attempt to defend a trial at all in such circumstances.

What else do I need to know about propensity evidence?

Generally, if you are facing multiple charges, the prosecution will rely on the propensity evidence rules to join your charges together and have a joint trial. This means the one jury hears all of your charges, which can significantly strengthen the case against you. It is important that you know the rules of propensity evidence if you are applying to sever the trials of different charges against you. Further, if evidence is admissible as propensity evidence, generally the court will not order severance of charges, as any prejudice that you suffer by their joinder is not as a result of impermissible prejudice, but because of the prejudice flowing from the strength of admissible evidence. It is important to understand these principles in a case involving multiple charges.

Conclusion

Propensity evidence can take many different and varied forms. The evidence is ordinarily prejudicial to an accused’s case, and can greatly strengthen the prosecution case. If you are facing a trial involving propensity evidence, don’t hesitate to contact James Jackson Criminal Defence for expert advice today.