Driver Lee Balkwell, 33, from Hornchurch, was found in a mechanism under the drum of the concrete mixer lorry in July 2002.

An inquest found his death was a result of unlawful killing through gross negligence.

Police ruled that Balkwell was the victim of a freak accident as he cleaned the lorry’s mixing drum.

But his father Les, a retired engineer, has long suspected murder and has accused police of a cover-up.

West Midlands Police have reviewed the case and recommended that Essex Police reinvestigate.

The details of the West Midlands report will not be released while investigations are carried out, Essex Police said.

A number of complaints against Essex Police officers involved in the original inquiry into the death are being investigated by the Independent Police Complaints Commission.

A team led by temporary Det Ch Supt Lee Catling of the Kent and Essex Joint Serious and Organised Crime Directorate will now conclude the investigative work carried out by West Midlands Police.

“Essex Police continues to keep an open mind on the cause of Lee Balkwell’s death,” a police statement said.

“The West Midlands report recommends particular investigative actions to be taken, disclosure of which could be prejudiced by making the report public.”

An inquiry by the Health and Safety Executive has been suspended pending the conclusion of the police investigation.