Published: 2 October 2007

	Dr David Hamer

UQ law academic Dr David Hamer has developed a model that aims to allow for more widespread acceptance of prior misconduct as evidence at criminal trials.

Dr Hamer, from the TC Beirne School of Law, argues that the Australian court system’s strict approach towards what is termed propensity evidence is unwarranted.

“Propensity evidence hangs on the proof that the defendant has committed prior misconduct,” Dr Hamer said.

“It could be prior convictions for similar offences, it could be allegations, or it could just be that the defendant has a connection with a whole sequence of events which would suggest that the defendant was responsible for those events.

In creating a model for the propensity inference Dr Hamer analysed the various parts that to determine the overall strength of the inference and whether it should be allowed to be admitted as evidence.

“The inference is dependent upon linking the accused to the other misconduct,” Dr Hamer said.

“Also, the present offence must be shown to share sufficient singularity with the other misconduct to indicate that the same person committed both sets of misconduct.”

Dr Hamer said the law had traditionally rejected the admission of propensity evidence for two reasons.

“First, for the jury to learn that the accused is a bad person may prejudice them against the accused,” he said.

“Second, there is a concern that the jury may be inclined to overestimate the value of such evidence.”

Dr Hamer said propensity evidence could add a significant probative element to a criminal case - in particular sexual assault cases - where the prosecution case frequently has a real need for probative evidence.

“Sexual assault cases are very serious and they are very hard to achieve a conviction on as it is hard to get evidence” he said.

“It is often the defendant’s word against the complainant’s word and the complainant has to be found to be much more credible to prove the defendant’s guilt beyond reasonable doubt.