A ‘crash for cash’ trial collapsed when the prosecution’s expert witness was revealed to be a disgraced former police officer.

Six people were accused of being involved in a plot to stage a collision between two cars in Wirral.

Ex-police sergeant James Boothby, 54, gave evidence on behalf of Crown Prosecution Service (CPS) Mersey-Cheshire.

But afterwards one of the defendants searched online and discovered Mr Boothby was sacked from Lancashire Police over his “dishonesty” in 2010.

Prosecutors at Liverpool Crown Court told the jury they could no longer rely on their expert and offered no evidence, leading to formal not guilty verdicts be entered.

Judge Norman Wright asked whether Mr Boothby told the CPS why he left the force, and said CPS divisions across the country should be informed of his background.

CPS Mersey-Cheshire would not tell the Lancashire Telegraph whether Mr Boothby disclosed his dismissal or if it had used him as an expert in other trials.

However, it said an investigation would be launched into how taxpayers were left footing the bill of an aborted five-day trial.

The area’s chief crown prosecutor Siobhan Blake said: “As in every case which does not proceed as originally anticipated, we will be undertaking a thorough review of all the circumstances in order to establish if there are any lessons to be learned.”

Lancashire Police said Mr Boothby appealed against his dismissal in 2011 and as a result was instead “required to resign”.

In a statement to the Lancashire Telegraph they confirmed: “The two charges which the appeal changed from dismissal to resignation were both in relation to honesty and integrity.”

Mr Boothby now works for George Parkinson Ltd, which provides forensic engineering services to insurance firms and legal professions.

His online CV does not mention being forced to quit Lancashire Police and merely states: “I left the force in 2010.”

It says: “I have attended and given evidence many times at both criminal and civil courts as an expert witness and have acted as a single joint expert and I am fully aware of my responsibilities in this area.”

The Independent Police Complaints Commission (IPCC) first investigated Mr Boothby in May 2008.

This related to a contract for the sale of recovered vehicles, which was awarded to a company run by his sister and brother-in-law.

In February 2008, the accident investigator applied to Lancashire Police to register an interest in the newly-established company.

Mr Boothby stated he would become a director of the firm and his role would be debt recovery and offering free advice.

The application was rejected, but the IPCC said the officer “made no secret of his plan” to take a role in the company on retirement.

A criminal charge against Mr Boothby, from Burnley, was dropped ahead of a trial in Liverpool in January 2010.

A disciplinary hearing in October 2010 found he created the company to benefit financially and breached the force’s code of conduct.

The IPCC said his conduct was “inappropriate” and his “actions were found to be dishonest”.

The collapsed trial related to an alleged conspiracy between December 1, 2010 and October, 31, 2014.

Raymond Cox, 55, of Park Road West, Birkenhead; Lawrence Murray, 64, of Paterson Street, Birkenhead; Stephen Rice, 43, of Carrhouse Lane, Moreton; David Russell, 67, of Woollam Drive, Ellesmere Port; Nicola Russell, 45, of Greenlea Close, Ellesmere Port; Paul Russell, 50, of Greenlea Close, Ellesmere Port; and Samantha Russell, 27, of Leven Walk, Ellesmere Port, were found not guilty of conspiracy to dishonestly make a false representation for gain.

Neither Mr Boothby or George Parkinson Ltd responded to the Lancashire Telegraph’s request for a comment.