British Nuclear Group Sellafield Ltd v Gemeinschaftskernkraftwerk Grohnde GmbH & Anor

The Employed Expert and how to Overcome a Lack of Independence

[2007] EWHC 2245 (Ch) TEDR Volume 12 Issue 3

The Facts

The case involved the calling of both factual and expert witnesses to provide evidence and some witnesses who gave both factual AND expert evidence.

The Issues

The issues in the case arose out of the agreement for, and provision by the claimant of, a nuclear fuel reprocessing service to the owners/operators of certain nuclear power stations and specifically one in Germany, being a reprocessing facility designed and built for the purpose at Sellafield, known as the Thermal Oxide Reprocessing Plant or “THORP”.

The case consisted of claims by BNFL that the defendants had failed to pay the full amounts due under invoices rendered to each of them pursuant to the Service Agreements, as supplemented by the Side Letters. Non-payment was admitted, but the defendants sought to justify non-payment, and to obtain recovery of alleged overpayment, under a series of defences and counter-claims.

The Decision

Relevant excerpts from the judgment of the Mr Justice Briggs are worthy of being directly quoted – by reason of the high significance of the issue of the independence of experts and how an expert may counterbalance a lack of independence by various means. The judgment also addresses how a witness of fact may, in appropriate circumstances, also act in the same case as an expert witness.

The relevant excerpts are set out below:

54. BNFL’s main witness was Mr Nigel Donaldson, called both as a witness of fact and as an expert. … I have kept in mind the need to distinguish between Mr Donaldson’s qualities as a witness of fact, and his qualities as an expert.

55. Upon analysis, his role may fairly be divided into three. First, he gave direct factual evidence about aspects of the design and appraisal of the THORP project in which he had been personally involved at the relevant time. Secondly, he provided largely hearsay factual evidence about a whole range of matters relevant to the RTR issue which he had collected from a detailed appraisal of the relevant documents, and from discussion with current and former colleagues at BNFL, several of whom did not give evidence themselves. Thirdly, he gave expert evidence in the form of his opinion as to the reasonableness of the conclusions reached by BNFL in reaching its view that THORP could reprocess a 7,000tU baseload in ten years.

56. Mr Donaldson graduated with first class honours in Chemical Engineering from the University of Bradford in 1976.

… [The judge then set out Mr Donaldson’s career history] …

60. … Mr Donaldson has the benefit of long and broad experience in the technical management of both Oxide and MAGNOX fuel reprocessing, relevant detailed personal knowledge of the design, commissioning and operation of the THORP plant, in particular the HEP, and as a continuing senior employee of BNFL, the ability by site visit, discussions with colleagues and document appraisal to refresh his memory on the details of the design and operation of THORP, not shared either by retired employees or by independent experts. By contrast however with Dr Wilkinson, Dr Jeal and Mr Smith, Mr Donaldson was not personally involved in the decision making process which led to BNFL’s commitment to the 7,000tU baseload for THORP in 1986.

61. Mr Donaldson was a factual witness of quite exceptional quality. In addition to providing a highly detailed account of the design of THORP and of the ancillary plant necessary for a complete Oxide fuel reprocessing system in his first witness statement, he evidently carried out the most through preparation for the provision of further factual information while being cross examined, and in numerous respects amplified his written account with substantial and precise further detail, wherever requested either by counsel or by the court. … In short, there appeared to be no aspect of the Oxide or MAGNOX reprocessing plants at Sellafield about which Mr Donaldson had not carried out the necessary preparatory work to be able to provide well researched and reliable factual answers to the technical issues thrown up by the RTR issue.

62. Mr Donaldson gave his evidence with care, patience, courtesy and a becoming lack of arrogance. His account of matters of factual detail was not successfully challenged at any stage in cross examination. He was also a highly articulate and patient teacher of technical detail to the uninitiated, including of course myself, and very occasionally counsel. All in all, he was a witness of primary fact in whom I found it possible to place complete reliance.

63. As an expert, Mr Donaldson started with an inevitable disadvantage in being a full-time employee of BNFL. Prior to the decision of the Court of Appeal in R (Factortame Ltd) v Secretary of State for Transport, Local Government and the Regions (No 8) [2003] QB 381, there were some who thought that full-time employment by the party calling him was a crippling disability for an expert, sufficient to render his opinions inadmissible as expert evidence: see for example Liverpool Roman Catholic Archdiocesan Trustees v Goldberg (No 3) [2001] 1WLR2337.

64. While it is now clear that full-time employment by a party is no longer a disqualifying characteristic for the giving of expert evidence, the lack of an independent relationship between the expert and the party calling him nonetheless remains a major factor going to the weight of the expert evidence, and one which it has been necessary for me to bear constantly in mind. Nuclear fuel reprocessing is a subject in relation to which it is no doubt difficult to find experts with relevant experience and qualifications, and although there are no doubt other reprocessing plants abroad, each will operate under its own commercial, technological and in particular regulatory constraints which render experience abroad intrinsically less valuable to the expert than experience at Sellafield itself. Furthermore, it may persuasively be argued that there is little substitute, in terms of a reliable perception of the realities, for a long day-to-day involvement in the process of the design and commissioning of the very plant under review.

65. Balancing those considerations, Mr Donaldson’s thorough preparation, wide ranging experience and personal involvement in the design, operation and maintenance of the THORP plant and its predecessor at Sellafield largely made up for his lack of de facto independence from BNFL. Furthermore, it appeared to me that he had both taken on board and resolved to take seriously his responsibility to the court as an expert witness. He was much criticised in cross examination for the perhaps argumentative tone of parts of his second witness statement, in which he took the defendants’ experts to task in robust terms for, as he regarded it, ignoring or failing to take account of material matters, including matters as to which he had given factual evidence available to them before they wrote their reports. That cross examination of Mr Donaldson was directed to persuading me that he was arguing a case rather than providing an objective opinion. I found his oral evidence to be an encouraging contrast to the signs of argumentativeness in his second witness statement. On the whole, he seemed to me to maintain both balance and objectivity under cross examination to an extent which led me to conclude that the apparent argumentativeness of parts of his second witness statement was more a matter of style than substance. …”


For once a case where an expert is not criticized but is praised by a High Court judge and whose expert evidence is found to be of high quality! This example shows when it may be appropriate for a witness of fact to be an expert witness. It also shows the judicial balancing exercise between a lack of independence on the one hand and, on the other hand, the use of objectivity, logic and diligence by the expert witness who happens to be employed by a party to the litigation.  The importance of day to day hands on experience of such a witness, especially in a specialist area of activity, was highlighted by the judge. The presumption of a reduction in weight to an expert who is not independent may accordingly be effectively rebutted by the expert adopting an independent-minded and rigorously analytical approach to the giving of his expert opinion evidence.

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