The use of Single Joint Experts (SJE) is often overlooked in dispute resolution, both in litigation and mediation - despite being a major innovation post the Woolf reforms. SJE’s are instructed by both sides in a dispute can bring a number of advantages and pitfalls.
A case by its nature may only require one expert, for example in uncontroversial matters such as completing specialised calculations or providing insights into common practices within the expert’s area of specialised knowledge. Methodologies may vary, but it is likely that any expert using the same methodology will arrive at a similar result and at least be familiar with alternative approaches.
Using a SJE brings advantages in terms of speed and cost as well as the potentially increasing likelihood of being granted permission to adduce expert evidence in the first instance. Additionally, the use of a SJE at an early stage of a dispute may help focus or narrow the issues and perhaps even avoid litigation altogether.
SJE’s are more often used in lower value disputes, but they can also be of use in higher value disagreements as well. Mr Justice Jackson noted in Quarmby Electrical, it may be that the use of adversarial experts would render a trial uneconomic, whereas the cost and speed advantages of a SJE would make it possible.
The use of a SJE at the outset of a dispute may potentially persuade a court to allow further expert evidence, subject to the reasons for wishing to instruct further experts being compliant and not ‘fanciful’. This might be when either or both of the instructing parties disagree with the SJE report or lose confidence in the SJE - though clarification of issues might be sought through further questioning as well. Further grounds for allowing permission to adduce further expert evidence are set out in Cosgrove v Pattison  by Neuberger J.
In a case where there is a range of possible opinions or the subject matter is highly subjective, a SJE can provide the range of possible opinions rather than adversarial experts, producing possibly just
two opposing views. Of course the use of experts at all is only necessary where they are essential to achieving resolution of a dispute in a timely and cost efficient manner.
Selection of a SJE may be problematic. Parties may not agree on whom to appoint and each side may prefer ‘their’ expert. Of course a reliable expert should continue to hold their own consistent views and be aware of opposing theories, regardless of which side instructs them. They should have the requisite skills and experience, and retain the confidence of both of the instructing parties. There are certain practicalities such as agreeing a joint letter of instruction and payment terms. It is possible that the instruction itself may introduce new problems as an opinion may vary depending on exactly what is being asked, but the very act of jointly drafting and agreeing an instruction between parties, can assist in focusing and narrowing the issues. All communications between the SJE and their instructing solicitors must be copied to both parties and comply with the requirements outlined in CPR35.
Normally an expert can coach lawyers, but not vice versa. This may be explaining technical aspects or clarifying common industry practices. The use of a SJE removes the ability of a solicitor to rely on that expert for informal advice. The use of a SJE also removes the need for the expert’s meeting or conference, but questions can be put to the expert to clarify issues in writing (subject to the requirements of CPR35.6). The questions must be proportionate, put to the expert only once within 28 days of service of the SJE’s report and be for the purposes of clarification of the report. It may be that the SJE is required to give oral evidence as well. If the Court grants this permission for cross-examination by both sides, it is to be ‘restrained’ to a degree. Furthermore an SJE can be used in mediation or arbitration to clarify issues and explain any consequences of a proposed course of action.
In general, it may be that SJE’s are less likely to be required to attend a trial, their contributions being usually written. This can speed up matters and their use also deprives counsel of any ‘hints and tips’ that may be passed to them in the form of a note or other communication from a single instructed party’s expert in the court. It could be argued that this removal of the coaching function of an expert is beneficial to the passage of justice, as neither party has the monopoly or benefit of the ‘best’ expert.
If the speedy and efficient resolution of a dispute is the aim, and the case is appropriate, the sharing and use of a SJE may be quickest way for the disputing parties to return to a less acrimonious discourse at the bar!