A judge has warned a former police officer that he may be jailed after being found guilty of assaulting a man he was trying to arrest.

Timothy Allatt, 33, formerly a Nottinghamshire Police constable, was today found guilty at Mansfield Magistrates' Court of assaulting Jake Bramley in the early hours of July 25 last year.

District Judge Diane Baker told Allatt that after hearing two full days of evidence she did not accept that he used reasonable force in detaining Mr Bramley who was being pursued by officers on suspicion of stealing a car.

She said she was satisfied by evidence that Allatt hit Mr Bramley, threw him against a wall and then dragged him face down on to the floor before kicking him in the chest area.

She told Allatt, who sat next to his solicitor and looked down at his clasped hands and up at the judge as she spoke, that in normal circumstances she would hand out a community order for an assault conviction but his case had aggravating factors.

"Those aggravating factors are that this was a sustained assault," she said.

"It was a sustained assault on a member of the public by a serving police officer."

She continued: "At this stage I cannot rule out a custodial sentence."

The judge told Allatt that when considering sentence she would take into account that he was a highly trained authorised firearms officer, that he had received four commendations in his 11 years as a policeman and that he was widely respected.

She told the court it was not said that Allatt caused all of Mr Bramley's injuries - he was treated as an in-patient at the Queen's Medical Centre in Nottingham for a collapsed lung and facial injuries following the incident - but she could not ignore the seriousness of his conviction and her duty to protect the public.

She added: "This was a gross breach of his position as a police officer."

She granted Allatt unconditional bail and adjourned his case to September 28 for pre-sentence reports.

Speaking outside the courtroom, Allatt's solicitor, Damian Kelly, said there would be no comment until he had been sentenced.

Last week the court heard that Allatt, who denied the offence, chased Mr Bramley through Sneinton, Nottingham, as he ran from police after they attempted to stop his silver Ford Fiesta as it was a suspected stolen vehicle.

Pc Daniel Moss, who was on duty that night, told the court that after being chased Mr Bramley was cornered by police and then Allatt assaulted him.

Mr Bramley was punched, grabbed, and kicked in the rib cage by Allatt, according to Pc Moss.

His account was to be believed over Allatt's, Ms Baker said.

Allatt said Mr Bramley, who was 22 at the time, looked "agitated" and "appeared to be in a fighting stance", which influenced the former policeman's actions at the time.

He said he carried out a "palm heel strike" as a distraction blow, which hit Mr Bramley on the left side of his face near his ear, and pushed and pulled Mr Bramley with both arms to bring him to the ground and make a lawful arrest.

He said he did not kick him, drag him, or throw him against a wall.

Mr Bramley was arrested and taken to Queen's Medical Centre at around 2.30am after he complained of chest pains.

Ms Baker said she did not find Allatt's account as he was on the witness stand to be plausible, nor did she accept that Pc Moss may have made up the allegation against him because he was derided by fellow officers after the incident for failing to keep hold of Mr Bramley when he managed to grab on to his tracksuit top as he ran past him that night.

Part of Allatt's evidence was that Pc Moss was not in the position he said he was at the time Allatt came into contact with Mr Bramley and could not have witnessed any alleged assault.

But Ms Baker said she was satisfied from evidence that Pc Moss could in fact have been close to Allatt at the time and could have seen his aggressive behaviour.

Allatt also did not tell the custody sergeant he had struck Mr Bramley when he was booking him in, nor did he record it on the standard police "use of force" forms that all officers have to complete when they have used force to restrain an individual.

During the trial, the court also heard that Allatt was dismissed in April this year after a police tribunal made a finding against him for unreasonable force.

But it was in relation to a separate matter and a different man who, the court heard, Allatt pushed against a wall after he got out of his police vehicle at speed in an aggressive manner.

Allatt has since appealed against the decision, but Ms Baker said it showed "bad character in the form of previous reprehensible behaviour".