Met Police's Superintendent Andrew Johnstone has been cleared of assault after he was taken to court for allegedly 'barging' into a colleague at a police networking event

A judge has hit out at prosecutors after a senior counter-terror police officer was put on trial accused of 'shoulder barging' a female colleague at a networking event.

Chief Inspector Andrew Johnstone was acquitted of assault by battery on Metropolitan Police colleague Penny Mills today.

The court heard Ms Mills did not see the incident, but felt she was jolted from behind as she attended a senior officers' leadership workshop at New Scotland Yard on January 17.

After Mr Johnstone was cleared today, Chairman of the bench Richard Blake questioned why the case had ever made it to court.

Mr Blake said: 'Judges can say inappropriate things at this point from the bench as to whether the prosecution should be brought.

'I do invite those who brought the prosecution to pause and consider the evidence we had in this case - whether this prosecution would have been brought if this happened in a tea room, at a bus station, and whether it was appropriate to bring this prosecution. I can say no more than that.

'I do invite people to consider the course of events which has led to this case coming before me.'

The court heard Ms Mills had already complained to bosses about Mr Johnstone's behaviour when he was their line manager in the Met's roads and transport policing command.

But she was overlooked for promotion to the senior role in favour of Mr Johnstone, a chief inspector qualified at superintendent level but without a posting at that rank, prosecutor Philip Stott said.

CCTV from the building did not show the moment of impact, the court heard.

Ms Mills told the court she was initially unaware a crime had taken place, and was only informed of the culprit when her colleague Detective Chief Inspector Claire Moxon said Mr Johnstone 'appeared to' crash into her deliberately.

She said Mr Johnstone then failed to apologise for his actions.

Chief Inspector Penny Mills (pictured in a file photo) felt she was jolted from behind as she attended a senior officers' leadership workshop at New Scotland Yard on January 17

Metropolitan Police's Superintendent Andrew Johnstone leaving Westminster Magistrates' Court, London today

Defending, Gerry Boyle QC said his client had spoken to colleagues at the networking event about a possible promotion - something that had possibly been put in jeopardy by any future misconduct hearings following Ms Mills' other complaints.

Mr Boyle said: 'If the prosecution case is to be believed, he (Mr Johnstone) took an opportunistic and career-threatening gamble of huge proportions (the shoulder barge) in the presence of others.'

Giving evidence from the witness box, Mr Johnstone said Ms Mills' complaints about his management style were 'malicious and vexatious' but denied prosecution suggestions that 'motivated' him to shoulder barge his former roads policing colleague.

Speaking of the incident, as Mr Johnstone went to get his bag and leave the room, he said: 'It (that route) seemed a natural way to go. There was a slight gap and that's why I went there.

'I absolutely did not shoulder barge Penny Mills when I went through that crowd ... that's not the kind of person I am - I didn't do it.'

An application to dismiss the case was made by the defence team, who said it was 'a sorry state of affairs' if someone could be guilty of assault simply by failing to apologise for something they did not realise had taken place.

But while the judge dismissed the application, he later acquitted Mr Johnstone, 51, of one count of assault by battery.

Mr Johnstone, a Met officer for more than three decades and of 'impeccable previous character' showed little emotion as he was told he could leave the dock a free man.

The alleged push happened when Mr Johnstone went to leave an event at New Scotland Yard

The Police Superintendents' Association questioned how the allegation ended up in a criminal trial.

PSA Professional Standards Co-ordinator Victor Marshall OBE said: 'We are grateful to the judge for seeing the inherent weakness in this case.

'We are deeply troubled that this case was ever considered for referral to the Crown Prosecution Service by the Metropolitan Police Service brought by the CPS, let alone brought to trial.'

He added: 'Andy Johnstone is a dedicated police officer with an unblemished 30 year career who is awaiting a well-deserved promotion.

'This case has caused considerable distress to him and his family.

'The Association will be seeking an urgent review as why this case was brought and it is hoped that the Met Police will now immediately conclude this matter.'

A Scotland Yard spokesman said: 'Ch Insp Johnstone is currently on restricted duties; this will be reviewed.'