Weatherford Global Products v Hydropath & Ors

[2014] EWHC 2725 (TCC)

Some salutary lessons for Experts

The Facts

This was a highly technical case (about which more later) in which the parties called significant amounts of expert evidence. It is not necessary for the purposes of TEDR to go through the allegations and the evidence; what is likely of interest to readers are two things:

1. the judge’s comments on trial preparation by the two legal teams, and the technical material they deployed, including via experts; and

2. the performance of the experts themselves.

Taking the second point first, the judge devoted a specific section of judgment (para 181) to the performance of the experts. His comments are illuminating:

• Dr Stevens: was the science expert engaged by the claimant. The judge described him as “by far the more qualified” as between him and his counterpart for the defendant. He was said to have a “weighty academic background” both as a physicist and an electrical engineer. The judge also noted, with evident approval, that Dr Stevens’ report and evidence were “clear and intellectually rigorous” and that he gave his evidence “in a very measured way; he was not prone to exaggeration.” The judge described him as “the most impressive expert in all respects” and “eminently credible.”

• Mr Roberts: was the Claimant’s electrical engineering expert, a chartered Electrical Engineer and a member of the Institute of Engineering and Technology. The judge noted he had “specific experience over many years in the oil and gas industry … involved in the design and specification of equipment and systems for use in that and other industries”, with over 20 years of practical experience in dealing with products relevant to the dispute. He was in the judge’s view “an impressive witness … quietly spoken but straightforward and down to earth.”

• Mr Senior: was called by the Defendant. Although a Chartered Physicist linked to Loughborough University the judge described his report and his evidence as being, “superficial and tentative.” In the witness box, the judge said he was, “straightforward, [but] nervous and inexperienced as an expert in litigation.” The judgment also identified a number of basic errors, including a failure in Mr Senior’s report to take the necessary steps of identifying all the documents and information with which he had been provided. To make matters worse, the judge noted that, “it was absolutely clear as his evidence unfolded that he had had regard to a much wider number of documents than the other experts,” He appears to have panicked in the witness box, being unable to remember what an abbreviation in his report referred to (it was the European Directive with which the case was concerned), and that since he was instructed “it [had] been a bit of a blur,” admitting other work had got in the way of his case preparation. To make matters worse, on the second day he told the court that he had had a change of opinion “in the shower before I got into my taxi this morning” such that he wished to resile from an opinion which he had jointly agreed with Dr Stevens in the joint statement, which the judge found surprising given, “the reason for the change was not obviously clear”; and “seriously undermined his reliability.”

• Mr Thomson: was the Defendant’s second expert. The judge described him as “fairly straightforward but again inexperienced as an expert in much the same way as Mr Senior”, “clearly inadequately briefed,” such that the judge concluded he was, “overall unimpressed with him.”

It is also worth noting two other passages from the judgment:

• First, the judge criticised the legal teams on both sides for the length of the witness statements, and the fact that they strayed into inadmissible “quasi-expert” areas; and

• Secondly and perhaps more importantly, the judge was at pains to say that,

“There seemed to be a belief that the judge was a specialist electronics and electrical engineer who would understand, without any explanation, precisely how the technology worked, how the alleged deficiencies came about, how the various suggested fixes might work, how the experiments were to be understood and how the final device … worked. Lawyers and experts need to explain if necessary in words of one syllable all these various matters.”


There are a number of points coming out of this case:

1. If you are going to be an expert, concentrate on the fundamentals. Knowing the area and having relevant experience in it will, obviously, be central – after all, it is what makes you expert. But not every expert in their given field is an “expert” in the sense that judges, lawyers and clients require. They are different skill sets. Work at both. Although plainly an academic, Dr Stevens plainly achieved this

2. In the same vein, it is no good being absolutely peerless in your field if you cannot communicate that clearly and forcefully in writing and under cross-examination. This takes real practice. Practicing cross-examination is hard (although not impossible), but report writing is a skill which can be learned – but only by really hard work to identify, appreciate and understand the key issues, marshal them into the right order, and then write a report which addresses them in a logical way. If this is done right, you will find that the report, in effect, writes itself. The really hard thinking comes in identifying and crystallising the right approach in the first place. Once that analysis has been done, your experience and qualifications should enable you to write a clear, concise answer. Remember; if you don’t start by identifying the right questions, you won’t get to the right answers;

3. Get the basics right; draft the report in a clear way, making sure the sources of your information are clearly stated.

4. Don’t rush and don’t panic. This applies to both the preparation for the case – where Mr Senior obviously came unstuck in taking too much on, and also to being in the witness box, where he appears to have got on the back foot and panicked. The result is that even the good points you have can be given away cheaply if you let nerves get the better of you. It is very likely here that one beget the other – Mr Senior got nervous and forgot things because he was not well prepared. Unforced errors in such circumstances tend to accumulate – see Mr Senior’s last minute, unexplained attempt to resile from the joint statement;

5. Mr Thompson appears to have had a different problem – lack of instructions from the client or the legal team. But he can only lay so much of that at their door; an inadequately briefed expert has to make it clear to his client that he is not being given enough time, or enough material, to do justice in his report, and that it is ultimately their case which will suffer as a result.

Lastly, the judge’s comments on the level of technical expertise that the parties evidently expected of him as a judge in a specialist division are illuminating, even if not especially surprising.

It’s a rare case where I don’t say to at least one expert instructed that I want them to stop and explain it to me again – this time, like I’m five years old. The good experts always can; and the best experts don’t even need to. There’s a great temptation if you are specialist in your field to assume that the listener has a level of familiarity with the subject matter that they just often won’t possess.

A convincing and clear expert report lays the groundwork for how a particular technical issue works before starting to describe what the client did right/the other side did wrong (and is all the stronger and more reliable for it).

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