Durham Police's Dominic Cummings probe is being treated as a 'critical incident' and being overseen by its most senior officers in bid to prevent reputational damage to the force

• Durham Police fears damage to its reputation in row over Downing Street aide 
• Dominic Cummings is facing backlash for decision to travel during lockdown 
• Force previously said it gave lockdown and isolation advice to his father
• Rowed back on Sunday, saying officers only discussed security concerns  

Durham Police has said that it is investigating Dominic Cummings' trip to the county during lockdown at the 'highest levels'.

The force says that the top aide's journey from London is being considered as a 'critical incident' and that the reason for treating it as such a high priority is due to the potential reputational damage the force is facing. 

The Times reports that Mr Cummings is being investigated for alleged breaches of lockdown law.

It will also assess whether or not he broke the highway code by driving when his vision may have been impaired by Covid-19. Gold Group, the police's version of Cobra, will discuss the case and how to proceed.

Detectives will track the movements of Mr Cummings' car and have already questioned a key witness.

Durham Police is worried about its reputation after it was included in the political row.

It found itself at the centre of the controversy after saying in a statement that it gave advice on lockdown guidelines and self-isolation when officers visited Mr Cummmings' father on March 31.  

On Sunday the force backtracked, saying that officers only gave security advice after learning that Mr Cummings was coming from London with his four-year-old son and wife.   

Ex-Greater Manchester Police chief constable Sir Peter Fahy said the PM's adviser would have been turned back if he was caught going between London and Durham.

Chairman of the Police Federation of England and Wales John Apter and Surrey Police also warned of the danger of hitting the roads with impaired vision.

Mr Cummings has come under fire for his 60-mile round trip to the beauty spot with his wife Mary Wakfield and four-year-old son on April 12.

Cabinet minister Michael Gove admitted he has also driven with bad eyesight as he leapt to the defence of his close friend this morning.

Sir Peter said officers were 'frustrated' by the Cummings case, adding it may hinder policy with the rules 'now very confused'.

He told Radio 4's Today programme: 'Clearly, number one, that's ill-advised as a means of testing your eyesight as to whether you're fit to drive, but again it's hard to see - unless there's some justification that that was to take daily exercise - how that was justified.'

Asked if it was a criminal offence, Sir Peter replied: 'It certainly appears to be against the Highway Code. It's not the way to test your eyesight, and put potentially other people in danger.'

What does the Road Traffic Act say?

• If a person drives a motor vehicle on a road while his eyesight is such (whether through a defect which cannot be or one which is not for the time being sufficiently corrected) that he cannot comply with any requirement as to eyesight prescribed under this Part of this Act for the purposes of tests of competence to drive, he is guilty of an offence.
• A constable having reason to suspect that a person driving a motor vehicle may be guilty of an offence under subsection (1) above may require him to submit to a test for the purpose of ascertaining whether, using no other means of correction than he used at the time of driving, he can comply with the requirement concerned.
• If that person refuses to submit to the test he is guilty of an offence. 

Source: gov.uk

He added 'it may well be that absolutely he'd have been turned back' by officers if they stopped him during the drive north from London in March.

Mr Cummings appears to have broken Section 96 of the Road Traffic Act 1988 during his trip.

It states: 'If a person drives a motor vehicle on a road while his eyesight is such... that he cannot comply with any requirement as to eyesight... for the purposes of tests of competence to drive, he is guilty of an offence.'

The top aide claims he used the journey on his wife's birthday to check his vision had recovered enough to drive back to London after suffering suspected Covid-19.

He had already travelled 260 miles from the capital to the North East two weeks before to stay at his parents' farm.

Road police officers warned it was a bad idea to take to road with impaired vision in the wake of the Cummings case.

Chairman of the Police Federation of England and Wales John Apter wrote on Twitter: 'Folks, I say this in all sincerity and as an important road safety issue.

'If you're feeling unwell and your eyesight may be impaired do not drive your vehicle to test your ability to drive. It's not a wise move.

'As a former road death investigator with Hampshire police I have investigated many serious collisions, including fatalities.

'Some of these were caused by drivers with impaired vision, this is a serious issue. Do not drive if your eyesight is impaired or you feel unwell.'

Surrey Police also weighed into the debate, posting: 'A driver's vision is very important.

'If you have any concerns about your eyesight don't drive, until you've sought the advice of a qualified optician.

'A driver must be able to read a standard number plate from 20 metres.'

The force also posted a picture of an eye test for Twitter users.

Sent out to bat for his Vote Leave ally this morning, Cabinet Office Minister Mr Gove told LBC radio he had done similar in the past.

Asked by presenter Nick Ferrari if he would have made the 60-mile round trip, he said: 'I have, on occasions in the past, driven with my wife in order to make sure, what's the right way of putting it.'