Expert Witness Conflicts of Interest: When a Surveyor Must Decline

An expert witness conflict of interest arises whenever a surveyor's connection to a property, a party, an adviser or an outcome could compromise, or appear to compromise, the independence of the opinion they give to the court. Under CPR Part 35 an expert's overriding duty is to the court, not to the client who instructs and pays them, so a surveyor who cannot demonstrate independence is of little use to anyone: the report is open to attack, the court may give it reduced weight or exclude it, and the fees spent on it are at risk. This guide explains what counts as a conflict, when it must simply be disclosed and when a surveyor must decline the instruction altogether.

Why independence is the whole point of expert evidence

CPR 35.3 states that an expert's duty to help the court on matters within their expertise overrides any obligation to the person instructing or paying them. Practice Direction 35 adds that expert evidence should be the independent product of the expert, uninfluenced by the pressures of litigation, and that experts should provide objective, unbiased opinions and should not assume the role of an advocate. Every Part 35 report ends with a statement of truth confirming that the expert understands and has complied with that duty.

For chartered surveyors the same rules arrive a second time through RICS. The practice statement Surveyors acting as expert witnesses makes independence a mandatory duty, and the RICS professional statement on conflicts of interest and the Rules of Conduct require members to identify and manage conflicts in every appointment. A surveyor who conceals a conflict therefore risks both the collapse of the evidence and a complaint to their professional body. The RICS expert witness requirements are summarised in a separate guide.

Common conflicts of interest for expert witness surveyors

Property disputes are local and the surveying profession is small, so connections are common. The situations that come up most often include:

• Prior involvement with the property. The surveyor carried out the original HomeBuyer Report, Level 3 survey, valuation or party wall award that is now in issue, or inspected the building for a lender, insurer or previous owner.
• A relationship with a party. The surveyor has acted for the claimant or defendant before, is related to them, socialises with them, or has a continuing commercial relationship with a developer, contractor, landlord or managing agent in the case.
• A relationship with the other side's adviser or expert. The two experts work for the same firm, trained together or have a business connection, or the surveyor has previously been instructed by the opposing solicitor on related matters.
• A financial interest in the outcome. The surveyor owns neighbouring property, holds shares in a party, or has been offered a fee that depends on the result.
• Moving from adviser to witness. A surveyor who spent months shaping one side's strategy as an expert adviser may struggle to show the independence a Part 35 declaration demands. The distinction is explained in the guide to expert witness vs expert adviser roles.
• Confidential information. The surveyor has seen the other party's privileged documents in an earlier role, for example as a party-appointed surveyor under the Party Wall etc. Act 1996 before the dispute moved to court.

Does a conflict of interest automatically disqualify an expert witness?

Not necessarily. In Toth v Jarman [2006] EWCA Civ 1028 the Court of Appeal held that the existence of a conflict of interest does not automatically disqualify an expert, but that any potential conflict must be disclosed as early as possible so the court can decide whether the evidence is admissible and how much weight it deserves. The key question is whether the expert's opinion is independent of the parties and the pressures of litigation.

The courts have shown how badly things go when connections are not disclosed. In EXP v Barker [2017] EWCA Civ 63 an expert had a long-standing professional relationship with the defendant that only emerged during the trial; the judge treated the evidence with great caution and the Court of Appeal upheld that approach. Opposing counsel will probe any connection during cross-examination of an expert witness, and an undisclosed one is far more damaging than a disclosed one. Where a connection exists but is minor, the usual course is to set it out in the report together with an explanation of why it does not affect the opinion.

When must a surveyor decline the instruction?

Disclosure deals with minor and historic connections. Some conflicts cannot be managed and the surveyor must decline. In practice a RICS surveyor will refuse an expert witness appointment where:

• their own earlier survey, valuation or award is the subject of the dispute, since nobody can give independent evidence on the quality of their own work in a surveyor negligence claim;
• they or their firm are already instructed by the opposing party on the same or a connected matter;
• they hold confidential information from the other side that is relevant to the issues;
• they have a direct financial interest in the outcome, whether through ownership, shareholding or a continuing business relationship;
• the proposed fee is conditional on the result. The RICS practice statement treats conditional or contingency fees as incompatible with the expert witness role, and the court's own guidance strongly discourages them; or
• a close personal or family relationship with a party or witness means independence could not reasonably be demonstrated.

Declining early protects everyone. A conflict discovered after a report has been served can mean a wasted fee of £5,000 to £15,000 on a straightforward matter, an application to the court for permission to rely on a replacement expert under CPR 35.4, and a slipped trial timetable. On a single joint expert appointment the bar is higher still, because both parties must be able to accept the surveyor as neutral.

How conflicts are checked before an expert witness is appointed

A proper conflict check happens before any fee is agreed. The solicitor or party supplies the full names of the parties, the property address, the names of the instructing and opposing solicitors, any insurers or funders, and the names of other experts already involved. The surveyor checks these against their own records and those of their firm, going back several years, and confirms in writing either that no conflict exists or exactly what the connection is. That written confirmation then feeds the independence paragraph of the Part 35 report. The step-by-step process is covered in the guide on how to instruct an expert witness surveyor.

The check should be repeated if new parties join the case, if a Part 20 claim is brought against a contractor or previous surveyor, or if the expert's firm takes on new clients during the litigation. Where the dispute concerns a party wall award or a contested valuation, the check should specifically ask whether the surveyor has ever acted in relation to the same building or for the same owners, because those are the connections most likely to surface later.

Appoint a conflict-free expert witness surveyor through Survey Merchant

Survey Merchant provides RICS surveyors as expert witnesses in construction defect, housing disrepair, dilapidations, boundary, party wall, valuation and surveyor negligence disputes across England and Wales. Because the panel numbers more than 2,400 surveyors, an expert can be matched to the discipline and the location without any prior connection to the property or the parties, and every candidate confirms a conflict check before CVs are released. The panel's experts work to CPR Part 35 and the RICS practice statement, with fixed fees quoted in advance and no conditional arrangements. Call 0204 579 8270 or use the contact page to request conflict-cleared CVs and a fee quote for your dispute.