The Guardian leads legal battle to show CCTV footage of Thomas Orchard being restrained and an emergency response belt placed over his face

Footage and images of a man with mental health problems who allegedly died at the hands of police and detention officers after a webbing belt was wrapped around his face can be revealed following a legal battle led by the Guardian.

A trial judge had refused to allow the release of CCTV footage showing Thomas Orchard being restrained and the ERB – emergency response belt – placed over his face.

But three appeal court judges said the video and still images of the incident could be released once the defence cases of a police sergeant and two civilian detention officers who are currently on trial for manslaughter was complete. The defence cases ended on Wednesday. Closing speeches and the judge’s summing up are due to take place over the next week.

The footage has been shown repeatedly during the trial of Sgt Jan Kingshott, 44, and detention officers Simon Tansley, 38, and Michael Marsden, 55, who all deny manslaughter.

Onlookers sitting in the public gallery at Bristol crown court have shed tears as it has been played.

The prosecution alleges that Orchard, 32, suffered a cardiac arrest and brain damage caused by oxygen starvation after the ERB was placed over his face.

But the three men on trial claim the belt was used because Orchard was threatening to bite them and insist their actions were proportional, legal and in line with their training.

The trial judge, Mr Justice King, warned the jury that the media may report on the CCTV footage. He told them not to pay attention to any reports.

Orchard, who had paranoid schizophrenia, was arrested on the morning of 3 October 2012 after being involved in a disturbance in Exeter city centre. Police were alerted and he was forced to the ground, put in restraints and carried to a van.

At Heavitree Road police station the defendants say Orchard was violent and threatened to bite them. Tansley asked for an ERB – an American-made restraint – to be brought in.

Mark Heywood QC, prosecuting, has told the jury an ERB is primarily used by police to wrap around a subject’s body at the chest, midriff or thighs. He said the belt could also be used as a “shroud” but should not be used as a “mechanism of securing or control” in the head area.

But the prosecution claims the belt was wrapped around Orchard’s face and he was lifted up to waist height in a face-down position. The court has heard how he was carried into a cell and placed on a mattress, where he was held for nearly five minutes with the ERB still over his face.

The footage shows how when the belt was removed and the officers exited the cell, Orchard was left lying face down on the mattress, apparently motionless. Officers and a custody nurse entered Orchard’s cell later to find he was not breathing and was in cardiac arrest. He died a week later in hospital.

Orchard’s mother, Alison Orchard, has told the court her son could be “abrupt” but she had not seen him have a “tantrum” for a decade before his death. She said she had never seen him bite.

Kingshott, who was supervising the restraint, told the court he accepted that the way Orchard was lifted face down with the webbing belt across his face, was “incorrect”.

He also conceded that a position Orchard was held in at one point was similar to a “hog-tie” – where ankles and wrists are secured behind the back – which could have made it harder for him to breathe.

But he insisted it was right for the ERB to be used on Orchard’s face because he claimed the detainee was threatening to bite the officers and because the belt was authorised for use by Devon and Cornwall police he believed it was perfectly safe.

He said the CCTV footage did not tell the whole story because although it records Orchard’s shouts, it does not pick up his quieter threats to bite the officers.

Tansley has said he was aware how horrible it was to be forced to wear an ERB and should have given Orchard a better explanation of what it was and why it was being used. But he said it was loose around the prisoner’s head.

Marsden told the jury the ERB was the only piece of equipment issued by Devon and Cornwall police to deal with someone who was attempting to bite or threatening to bite. But he said its use as a “spit hood” was “merely tagged on” to the course on its utilisation and formed a “very limited” part of it.

Three other newspaper groups – Associated, the Times and the Independent – were also involved in the legal battle to secure the release of the footage. The appeal court ordered that the media could not post any report of the trial on Facebook and should not permit readers to post comments on reports.

The trial continues.