A row between the Metropolitan Police Service and doctors who care for detainees in police stations is threatening to undermine criminal trials and harm the treatment of those in custody, medical practitioners say.

New contracts for the Met’s 150 forensic medical examiners (FMEs) come into force this week. The Met says the contracts will allow it to deploy doctors more efficiently.But doctors say the reforms could jeopardise their ability to give independent evidence in court, as the contracts make them more akin to employees. Another concern is that the contracts give police control over access to medical records.Only 60 of the FMEs have signed the contract, causing a shortage of cover at police stations.

Dr Michael Wilks, a senior FME who has been leading the doctors’ negotiations with the Met, said inadequate cover would cause delays in FMEs attending police stations, which could lead to evidence being lost or ruled inadmissible. The quality of care given to detainees could also suffer, he said.

Ian Kelcey, chairman of the Law Society’s criminal law committee, said the impasse could have ‘grave implications on the outcome of cases. FMEs are crucial in that they need to be on hand and available to assess defendants’ suitability for interview, the appropriate gathering of evidence, and to be available to advise the police at an early stage’.

The Met said all 32 London boroughs and their detention facilities would be covered by either FMEs who have signed the new contract or by FMEs provided by an outsourcing contract.