A former policeman’s assault case had to be adjourned because vital film footage was missing due to an unrelated police investigation into alleged misconduct.

Matthew Essex was set to stand trial for five alleged attacks on his girlfriend – twice while driving on the motorway.

But on Wednesday the trial had to be halted as some key evidence, downloaded mobile phone footage, had not been provided to the court.

Essex’s solicitor Anastasis Tasou said that the phone “contains material which would seriously undermine the Crown’s case.”

Kirklees magistrates agreed to adjourn the trial after prosecutor Ben Crosland told that the problem had been caused following the shut down of the property storage at Huddersfield Police Station.

He said: “Sometime after September there was a problem with the property stores at Castlegate Police Station.

“There was an investigation into alleged misconduct in the administration of the property stores and that led to a shut down.

Former West Yorkshire police officer accused of attacking his girlfriend on M62 'like a maniac'

“That’s led to a massive backlog and that’s the reason for the delay.”

Essex, of College Avenue in Lindley, denies five allegations of assault by beating.

The former West Yorkshire policeman is accused of hitting the victim in the head as he drove his car “like a maniac” towards Manchester Airport.

During another journey to Xscape crazy golf, the 36-year-old allegedly punched her five times.

Huddersfield Police Station.

Then during an alleged incident outside a sandwich shop, Essex is said to have ordered the victim into his car before grabbing hold of her dress and ripping it.

Four witnesses, including the complainant, attended at the Huddersfield court to give evidence curing the trial which was due to last for a full day.

Mr Tasou told magistrates that while he was “ostensibly ready for trial” there was a “crucial piece of evidence” which had not been received in time for the hearing. He explained that this was the download of a mobile phone seized by police which “contains clear photographic and videographic evidence which blatantly undermines the allegations.”

Mr Tasou acknowledged Mr Crosland’s point that there had been failures on both sides to obtain this material, but told magistrates that without this it was “not in the interests of justice” to proceed.

At one point during the lengthy discussions, Mr Tasou withdrew himself as Mr Essex’s solicitor as magistrates said that the trial should still go ahead.

But following Mr Crosland’s explanation about what happened with the phone footage, they granted an adjournment until March 29 to allow time for the downloads to be disclosed as evidence.

Essex was bailed with conditions that he does not contact the complainant and stays out of Calderdale.