Restraint techniques that have an 'ever-present' risk of death

Restraint techniques used to deal with extremely aggressive people can substantially restrict their ability to breathe, an expert has told The Bureau of Investigative Journalism amid calls for fresh scrutiny of the way some of the most disturbed detainees are held by police.

Dr John Parkes, a restraint expert at Coventry University, said those pinned down by police were likely to struggle more as they fought for air. "In the cases in our research, we have used no extreme force, but in some cases have restricted their ability to breath by up to 80 per cent...That was done with very, very little force indeed," he said.

The police continue to use restraint techniques that have been attributed to deaths stretching back nearly two decades. Guidelines do not bar any particular holds but say that the use of force must be lawful, proportionate and necessary.

One technique is so-called "prone restraint", which involves forcing a suspect face down on the floor, cuffing their hands behind their back and then putting pressure on their torso, shoulders and neck. Stricter guidelines on the use of prone restraint in prisons were brought in during the mid-1990s following a spate of restraint deaths. Prison service rules now state that "pressure should not be placed on the neck, especially around the angle of the jaw or windpipe. Pressure on the neck, particularly in the region below the angle of the jaw (carotid sinus) can disturb the nervous controls to the heart and lead to a sudden slowing or even stoppage of the heart."

A 2004 Metropolitan Police review recommended that prone restraint should be avoided or minimised, but, according to 2006 national guidelines, it is still not banned.

Deborah Coles, director of Inquest, a charity that deals with cases involving deaths in custody, believes there are "fundamental problems" in the effectiveness of police training in restraint. "My fear is ... that there is the ever-present risk of death and serious injury and that this is an issue that does require proper public and parliamentary attention as a matter of urgency."

Simon Pountain, the Met Commander responsible for self-defence and restraint at the Association of Chief Police Officers, said: "Where an individual is violent and represents a danger to themselves and the public, the police are rightly expected to restrain them for their own safety and to protect other members of the public. Foremost in officers' minds is the safe resolution to volatile situations, not a medical diagnosis."