The TUC has called for work-related deaths to be treated as manslaughter from the outset.
In a submission to the National Liaison Committee of regulators and enforcers (NLC) it said the committe members should undertake joint training of officers on how to investigate work-related deaths.
The NLC comprises The Association of Chief Police Officers, the Health and Safety Executive and the Crown Prosecution Service.
It was created in 1998 to agree a procedure for how its three members would liaise on workplace deaths.
It recently began a review of the procedure and invited submissions.
The TUC has also called for specialist counsel to be called on to advise the investigators and take forward any resulting prosecutions.
It has asked for every work-related death to be investigated jointly by the police and the Health and Safety Executive and treated as manslaughter, until manslaughter can be eliminated.
Rail unions were the most heavily involved in assisting the TUC with the submission.
