BREACH OF the rules governing the use of expert witnesses has contributed to the fact that the Health & Safety Executive must pay £680,000 towards the cost of its investigation into the HEX collapse and its prosecution costs.
The error also earned the HSE and consultant engineer WS Atkins a strong rebuke from the Heathrow Express trial judge, Mr Justice Cresswell.
The ruling followed dramatic revelations at the start of the trial by Geoconsult's defence team. It claimed that large parts of a report written by the HSE's primary expert witness, WS Atkins head of tunnelling Guy Lance, were in fact drafted by HSE principal inspector Martin Thurgood.
The law requires that expert evidence is independent, unbiased and must not omit any information that might detract from its opinion.
During the trial defence advocate Arthur Marriott QC successfully argued this point, and told the court: 'Mr Lance effectively became a prosecution advocate.'
The HSE said in its defence that the problem had been the result of a misunderstanding of the rules. It had employed WS Atkins during its investigation and Lance and Thurgood had been in constant communication.
In his sentencing, the judge explained it had emerged that in Lance's independent report '81 pages out of 122 contained contributions' from the prosecution team - 'sometimes extending to whole pages.' This prompted HSE to abandon the report and expert witness altogether and almost caused the trial to collapse after one week.
The judge ordered Geoconsult and Balfour Beatty to pay £100,000 each towards the costs of the HSE investigation. This fell well short of the £880,000 the HSE spent on the four-
year investigation. This cost included £250,000 paid to Atkins for its work during the investigation - much of which was ultimately abandoned.
'In my opinion there is an important need on the part of the courts to make clear from time to time what is expected,' said Judge Cresswell.
He said the problems resulted from the HSE's failure to give clear instructions to Thurgood on the use of expert evidence and a failure by Lance to understand the duties of the expert witness.
'The result is that the defence incurred unnecessary costs,' he concluded.
'We all have something to learn from this incident,' said Thurgood, speaking after the trial. 'We certainly do (have something to learn) in the way we use expert witnesses.'
As NCE went to press WS Atkins said it was unable to comment on the situation because of the possibility of an appeal.