Seven expert witnesses who fabricated evidence about the cost of replacement hire cars for motorists in road crashes – leading millions in losses and hundreds of redundancies at Accident Exchange - have been jailed.

High Court judge Mr Justice Supperstone said they had been involved in “a very serious perversion of the course of justice” and imposed prison sentences of as much as 13 months.

The seven men and one woman worked for Autofocus Ltd and committed “perjury on an industrial scale”, the judge said.

Autofocus provided evidence on behalf of insurance companies to dispute the daily rate the hire car specialists Accident Exchange could claim for providing replacement vehicles, reports The Guardian. 

The expert witnesses, who are estimated to have saved insurance companies millions of pounds, were found guilty of contempt for untruthfully stating that they had checked the spot rates for comparable vehicles within a locality and that the Accident Exchange charges were inflated and excessive.

In six cases, the experts perjured themselves when they gave evidence on oath when disputes went to court, said the judge.

Former Accident Exchange chairman and chief executive Steve Evans (pictured) brought a private prosecution for contempt after the City of London Police said it didn’t have the resources to analyse a key piece of evidence – an external hard drive containing Autofocus records of key phone calls and documents copied by the company’s liquidator.

Evans estimated there had been 30,000 instances affected by the defendants signing false statements of truth after making rates reports.

Their dishonesty hit Accident Exchange’s share price, leading to losses of more than £100 million, with 300 people made redundant, the judge said.

Mr Justice Supperstone jailed the seven on Friday and ordered them to pay a total legal bill that could be as high as £1.5m.

He declared: “The evidence that was involved in the systematic, endemic fabrication of evidence in which the defendants and each of them knowingly and actively participated throughout the material time is overwhelming.”

The Autofocus expert and team leader Nathan George Broom, from East Anglia, was jailed for 10 months; the company director Elaine Carlton Walker, from Gloucester, received 13 months and one week; and the team leader Duncan Carl Sadler, from Oxford, was jailed for 12 months.

Andrew Watts, from Wirral, Liverpool, was jailed for seven months; David James, from Wirral, for eight months; Laurence Gray, from Oxford, for six months and three weeks; and Keel Broom, from Beccles, Suffolk, for six months.

Unlike the other six, although guilty of contempt in making false statements, Broom never perjured himself by lying in court.