A retired expert police trainer has told the trial of an officer accused of murdering ex-footballer Dalian Atkinson he “would never train” colleagues to use a foot to restrain someone’s head on the ground.

Ian Mills, who had 28 years in policing, also told Birmingham Crown Court on Friday he had never trained officers to kick people in the head.

“You can’t train it, it serves no purpose (to train it)… most people can deliver kicks, low down,” he said.

Prosecutors claim West Mercia Police Constable Benjamin Monk, who denies murder and manslaughter, used unlawful and unreasonable force during a final 33-second firing of his Taser, and by then kicking former Aston Villa star Atkinson twice in the head.

Mr Atkinson, who was then handcuffed near his father’s home in Meadow Close, Telford, Shropshire, in the early hours of August 15 2016, later died in hospital.

Monk, who previously described his kicks as not-targeted and “instinctive”, told a jury he was “terrified” that he and his colleague “were going to die” during the encounter.

He has claimed an “unpredictable and erratic” Mr Atkinson, who also played for Sheffield Wednesday and Ipswich Town, said he was “the Messiah” and was threatening to take the officers “to the gates of hell”.

Monk’s kicks were delivered with enough force that the marks from the officer’s right boot were left imprinted in the former sportsman’s forehead, jurors have been told.

Previously giving evidence in his defence, Monk, 43, has also claimed he could not remember having his boot on Mr Atkinson’s head, after tasering the man.

That was despite being seen with his foot “resting” on the 48-year-old, by two other police officers arriving at the scene, the court heard.

You can't train it. It serves no purpose (to train it).

Giving expert evidence for the defence, Mr Mills, a police use of force and Taser training expert, was asked by Monk’s barrister Patrick Gibbs QC if he had ever trained officers “to kick people in the head”?

He replied: “No. The reasons are two-fold, really.

“If they’re both standing then it would take a great deal of practise, training and martial arts ability, to kick a standing subject while you are standing.

“If the subject is on floor, just about anybody could deliver kick to any part of the subject – but it wouldn’t be easy to train or safe to train to kick a role-player to the head in the training environment.

“You can’t train it. It serves no purpose (to train it).

“Most people can deliver kicks low down – they just can’t, high up.”

Mr Gibbs then asked: “Is the head or any part of the body ruled out as target area?”

Mr Mills replied: “There’s no part of the body ruled out, there’s just medical implications related to each part of the body and the tactics used on each part of the body.”

Asked who must justify the tactics used to bring a person under control, whether making an arrest or detaining a person, Mr Mills said that duty would fall to the officer making the decisions.

He said: “It has to be the officer, based on the circumstances in which they saw it.”

Mr Mills completed an expert report on aspects of use of Tasers and use of force, in which he cited accepted police training doctrine.

Mr Gibbs read to the jury the following passage, cited within Mr Mills’ report, which stated: “The nature of policing is so diverse it’ll never be possible to document guidance to cover every eventuality.

“For this reason there’s always occasions when individual officers resort to techniques and tactics not described in this manual.

“In such circumstances the actions of officers will not necessarily be unlawful, provided they have acted reasonably and within the law.

“The individual concerned must be prepared to account for their decisions and show they were justified in what they did.”

Mr Mills, a former member of the College of Policing’s 12-strong Taser National Practitioners group, was also asked about a download of the X26 model Taser that Monk had used on Mr Atkinson.

Jurors have previously heard that Tasers deliver an electrical charge to a person, only if still loaded with a replaceable cartridge.

On the night, Monk used all three of the cartridges he was carrying after claiming the first two “Taser strikes” were “ineffective”.

Jurors previously heard that data extracted from the device showed on the third occasion the Taser was used, bringing Mr Atkinson to the floor, it discharged an electrical current for 33 seconds – over six times longer than the default five-second trigger period.

Mr Gibbs asked Mr Mills “can you tell from the (device data) download, whether there was a cartridge fitted at the time?”

Mr Mills told the jury: “No.”

Turning to the allegation Monk was seen resting his foot on Mr Atkinson’s head, by his own colleagues, Mr Gibbs asked the experienced trainer: “Have you ever seen that trained to an officer as something they should do?”

He replied: “Pinning the head, yes – but not with the foot.”

Mr Mills said an officer might instead use their “hands” or “shin”, “in order to prevent injury and restrain someone – if someone is self-harming, banging their head on the floor, during extractions, it’s common to restrain the head to the floor.”

Mr Gibbs then asked: “And (restraint of the head) with the foot?”

Mr Mills replied: “I’ve never trained it, I would never train it and I’ve never seen it.”

Monk was also alleged by one eyewitness member of the public to have been seen “stamping” on Mr Atkinson during the altercation.

Asked if that was a trained technique in his experience, Mr Mills said “no”, adding once again, however, it was not ruled out as a potential tactic, so long as an officer could justify the use of force.

Prosecutors have claimed Monk has “exaggerated” his fears of Mr Atkinson that night, kicking and tasering the former striker in “anger”, and had since “sought to deliberately lie” to cover up his “use of excessive force”.

Monk, then of 14 years’ experience, is on trial alongside fellow officer Mary Ellen Bettley-Smith, 31, also his then lover.

She denies a charge of assault occasioning actual bodily harm, by using her force-issue extendable baton on Mr Atkinson during the incident.

The trial continues.