2 Admissibility of expert evidence

There are a number of rules, primarily common law, that prescribe when expert evidence will be admissible. Some of these rules apply to all evidence, but others are specific to expert evidence. For example, the concept of evidential 'weight' means how much influence the evidence will have on the fact-finder's decision. This applies both evidence from lay witnesses and expert witnesses, though often expert evidence will tend to carry more weight overall.

In the following sections, you will be introduced to some of the key admissibility rules concerning expert evidence, namely relevance, assistance, reliability, expertise and hearsay.