Civil claims often require expert evidence to allow the court to understand the issues at stake. Take for example a construction dispute over a poorly built conservatory that now leaks when it rains. It may seem obvious to you that the builder was negligent. But the builder will no doubt argue that they followed all the proper standards in respect of their work and materials, and if the conservatory leaks then it must be due to something out of their control.

Judges are not experts in construction. They need the claimant to provide evidence from an expert of precisely what standard the builder may have breached, how they breached it, how that caused the damage and loss complained of, and why in the expert’s opinion the builder is liable.

Courts have very stringent rules about who may act as an expert witness, and in what form they must provide their evidence, because although an expert has a duty of care to the party instructing and paying them, this is overridden by their duty to the court to provide independent evidence within their area of expertise.

Appointing an expert witness is one of the most important aspects of litigation your solicitor undertakes on your behalf. A good, properly compliant report from an authentic expert in their field helps the court understand your claim, improves your chances of winning at trial, and perhaps more importantly, may persuade your opponent of your seriousness and the soundness of your claim and induce them to settle before trail, cutting your costs risk and saving you time and stress.

The other side of the coin is that providing poor or unsuitable expert evidence can be have disastrous consequences.

One recent high-value case came unstuck because it turned out that the expert engineering firm was effectively giving an opinion on their own work, and had an obvious interest in their instructing party winning the case. Another recent case involved a firm of accountants giving an opinion on an area of business in which they were not deemed to be sufficiently expert.

Failed expert evidence is bad news for the instructing party because, even if you do not lose your case, if your expert evidence is ruled inadmissible or even treated with caution by the court, you will struggle to persuade the court to order your opponent to pay your expert’s fees. In the event that you lose as a result of poor expert evidence, you may have to pay all of your opponent’s costs, including experts’, solicitors’ and barristers’ fees.

If this happens you may be forgiven for looking for someone to blame – and sue. You could sue the expert, but suing experts is a relatively new phenomenon so there isn’t a huge body of case law to base a claim on. And anyway wasn’t it your solicitor who picked the expert and provided them with all the information and instructions?

Solicitors are aware that they must exercise reasonable skill and care in all aspects of conducting litigation, including appointing experts, or they could be negligent. So when you get your friend who does a bit of building work to quote for remedial work on your leaky conservatory, and he tells you he could throw in a report to back up your claim because he knows the job now and he has your back, don’t be surprised if your solicitor politely declines.

Your solicitor will be protecting your interests in appointing a suitable expert. Even if they are more expensive than your friend, your chances of winning your case, and being able to claim your expert’s and all other fees for your opponent, will be greatly increased. Then you and your solicitor will remain friends.