Auditors trying to assess whether medical experts can join a personal injury diagnosis scheme say they are being mistreated by the subjects of their inspections, it has emerged.

The MedCo board, which oversees the government-backed scheme for soft tissue injury diagnosis, today revealed it has observed 'unacceptable behaviour’ toward auditors checking member organisations. MedCo also stated it has received 'unjustified' complaints about members of the audit team.

Auditors have spent this year testing whether medical reporting organisations meet new criteria for being involved with the accreditation scheme. The new rules were introduced after some medical companies flouted the spirit of the scheme by creating numerous shell organisations, in order to appear more often on searches for experts to diagnose injury claims.

The MedCo board says incidents of unacceptable behaviour are becoming more frequent, and warns it 'will not tolerate' such actions.

The statement adds: 'MedCo auditors have therefore been instructed that if, during the audit process, they are subjected to any behaviour they consider to be unacceptable they are, with the agreement of the head of the MedCo audit team, to abort the audit and report the matter to the board.'

Any MRO found to have behaved improperly to auditors will be immediately suspended from the system until an audit has been rescheduled and completed. A re-audit fee of £500 will be charged and the process will take up to three months.

MedCo, which was introduced by former justice secretary Chris Grayling to cut financial links between lawyers and medics, introduced new rules last autumn requiring all aspiring MROs to provide documented assurances they are independent, properly staffed and resourced, and ‘directly and solely’ responsible for all work associated with receiving instructions.

Within a month, 134 'shell' companies were suspended from the system and removed from search results.

Top-tier organisations, which appear more regularly in searches, must have the capacity to process at least 40,000 independent medico-legal expert reports each year. If they are new they must show an appropriate business strategy and operational functions to manage such a workload.

They must have contractual agreements with at least 250 individual active MedCo-accredited experts, who are located in 80% of the postcodes in England and Wales.