When can you rely on expert evidence in court proceedings?
You might think it is helpful to your case, but that may not be enough to persuade the court. It is worth remembering that you can instruct an expert at any time, but you can only rely on that evidence in the proceedings, if the court gives permission. Also without that permission, you may not be able to recover the expert’s costs if you are successful.
Before giving permission, the court will want to see an estimate of the expert’s costs and the issues the expert will address. The court rules say that expert evidence will be restricted to that which is reasonably required to resolve the proceedings.
What does this mean in practice?
The courts tend to look at whether the expert evidence is necessary. In a recent case*, the High Court made a distinction between evidence that is necessary and evidence which is of marginal relevance. If the evidence is necessary, this means that a decision can not be made without it. That evidence will usually be permitted.
On the other hand, if the evidence is of marginal relevance only, the court may be able to decide the issue without it. In those cases, the court will look to strike a balance and will consider the proportionality of the costs of allowing that evidence as well as a number of other factors. These include the value of the claim, the effect of a judgment either way on the parties, who is to pay for the commissioning of the evidence on each side and the delay that might result.
So, helpfulness is not the only factor. If the court decides that the evidence is not necessary, the evidence might be allowed if it is helpful in understanding an issue that is central (rather than peripheral) to the case.
When considering case management decisions like this, the courts are required to give effect to the overriding objective of dealing with cases justly and at proportionate cost. In this case, the Judge did not consider that there was any tension between the overriding objective and the restriction of expert evidence. But he did note that the court should not be “over-zealous” in excluding evidence in order to save time and cost.
This case concerned a pensions dispute with significant financial implications. The claimant wanted to rely on expert actuarial evidence which the High Court allowed after an appeal. The case reflects the difficult balance the courts have to achieve.
If you do obtain permission to rely on expert evidence, remember that the court rules impose obligations on that expert, including that the expert has an overriding duty to the court.
For more information, email firstname.lastname@example.org.
* British Airways Plc v Paul Spencer and 11 Others (Present Trustees of the Airways Pension Scheme)  EWHC 2477 (Ch)