Police plans to employ full-time custody nurses at police stations could undermine the independence of medical provision and lead to miscarriages of justice, criminal and mental health lawyers have warned.

The Metropolitan Police Authority (MPA) is recruiting nurses to be permanently based at police stations, on a 24-hour basis. They will be responsible for assessing whether detainees are fit to be interviewed, as well as collecting forensic samples and giving medication. While doctors – Forensic Medical Examiners (FMEs) – will still attend police stations when required, they will be peripatetic and not permanently based at police stations. The aim is to ensure speedier medical assessments and increase the number of cells available by processing detainees more quickly.

Richard Charlton, chairman of the Mental Health Lawyers Association, said the nurses would be employed directly by the MPA, raising concerns about conflicts of interest. ‘The move signals a downgrading of the evidential procedure, with nurses exposed to pressure from hard-pressed colleagues to declare someone mentally fit for interview,’ he said. ‘It’s a backward step and will certainly result in miscarriages of justice.’

Malcolm Fowler, a criminal defence partner at Birmingham firm Jonas Roy Bloom, said: ‘It’s the same old story of de-skilling in the name of cost saving. The nurses will get a light dusting of training and then be expected to make complex appraisals of a detainee’s fitness for interview.’ Dr Peter Green, a London FME for 28 years, said the MPA’s plans were good in principle because teamwork was central to modern medicine. ‘But I have real fears about nurses working unsupervised,’ he added. ‘They have not had the same training as doctors to make a multitude of diagnoses and are sure to come up against serious and complicated cases that are beyond their competency.’

A spokeswoman for the MPA said a permanent team of healthcare professionals at police stations would ‘significantly’ reduce delays and be ‘safer’. The MPA is to begin training and deploying the nurses in Westminster, Lewisham and Croydon before the end of this month and at six further locations from December.