The American woman accused of killing Harry Dunn was a CIA agent, The Mail on Sunday can reveal.

Fugitive mother-of-three Anne Sacoolas, who fled Britain after crashing into the teenager’s motorbike outside an air base last August, is understood to have served as a senior spy.

British Ministers and officials are aware of Mrs Sacoolas’s career in espionage, but she was not declared as an agent when she came to the UK alongside her intelligence officer husband Jonathan.

Fugitive mother-of-three Anne Sacoolas - who is accused of killing Harry Dunn - was a CIA agent, The Mail on Sunday can reveal. Pictured: Mrs Sacoolas back home in Virginia last week, where she was pictured filling up her car

Harry’s mother Charlotte Charles said that, following our revelation, ‘things are now beginning to fall into place’ as to why the US government was blocking her extradition to face justice.

Mrs Sacoolas’s right-hand drive Volvo is alleged to have been on the wrong side of the road when it collided with Mr Dunn last summer.

Mystery still surrounds the exact circumstances of how the Sacoolas family were able to flee in the days after the crash, but the US government claim they notified the Foreign Office that they were leaving.

Mrs Sacoolas has been charged over the fatal accident outside RAF Croughton and has apologised for 19-year-old Harry’s death, but is refusing to return to Britain.

Mrs Sacoolas has been charged over the fatal accident outside RAF Croughton and has apologised for 19-year-old Harry’s death, but is refusing to return to Britain. Pictured: Harry Dunn

However Harry’s family claimed there had been a ‘cover up’ and have vowed to keep fighting to bring her back to Britain.

Multiple sources in both Washington and London have confirmed Mrs Sacoolas’s CIA background, but the American government insist she was not spying on Britain.

Harry’s mother Charlotte Charles (pictured) said that, following our revelation, ‘things are now beginning to fall into place’ as to why the US government was blocking her extradition to face justice

US government sources said Mrs Sacoolas was ‘not active’ in the UK, although a security source said: ‘You never really leave the CIA.’

One government source even claimed Mrs Sacoolas had been ‘more senior than her husband’ in the US intelligence community.

Ms Charles told The Mail on Sunday last night: ‘Things are now beginning to fall into place. In our deepest, darkest hour, we could not understand how anybody could just get on a plane after such a catastrophic crash and leave a devastated family behind.

‘We have also found it impossible to figure out why the US administration has behaved in the lawless way it has in harbouring Anne Sacoolas. But no one is above the law. Whether or not you are a CIA officer, a diplomat or anyone else, the Vienna Convention states that you must abide by and respect the rules and regulations of the host country.

‘Her leaving, and the US government protecting her and refusing the extradition request, is nothing short of a disgrace and we will not stand for it. Whether she is CIA or not, she must come back and I will not rest until she does.’

Mrs Sacoolas’s right-hand drive Volvo is alleged to have been on the wrong side of the road when it collided with Mr Dunn last summer. Pictured: Mrs Sacoolas

Our revelation comes at a time of strained diplomatic relations between the UK and America over Boris Johnson’s refusal to ban Chinese tech giant Huawei from building part of Britain’s 5G phone network, as well as the US refusal to extradite Mrs Sacoolas.

In contrast, Home Secretary Priti Patel last week gave the green light to extradite Mike Lynch, one of Britain’s most successful businessmen, to face a US fraud case. Her decision opened up Tory divisions, with former Cabinet Minister David Davis using an article in The Mail on Sunday – on the facing page – to brand the US-UK extradition arrangements ‘a bad treaty’.

The UK and US governments insist that, at the time of the accident, Mrs Sacoolas had diplomatic immunity while her husband was working as technical staffer at the Northamptonshire air base. The Foreign Office confirmed that Mrs Sacoolas ‘was notified to us as a spouse with no official role’ – but senior Whitehall figures have confirmed they knew of her CIA history.

Harry’s family claimed there had been a ‘cover up’ and have vowed to keep fighting to bring Mrs Sacoolas back to Britain. Pictured left to right: Tim Dunn (Harry's father), Charlotte Charles (Harry's mother), Tracey Dunn and Bruce Charles

The US State Department declined to comment on our revelations yesterday, saying only: ‘The driver was the spouse of an accredited diplomat to the United Kingdom.’

In December the Crown Prosecution Service announced it was charging Mrs Sacoolas over Harry’s death, but her lawyers said the prospect of 14 years in prison was ‘not proportionate’ for what was ‘a terrible but unintentional accident’.

And last month the US government turned down an extradition request, to the devastation of Harry’s family.

Last month the US government turned down an extradition request, to the devastation of Harry’s family. Pictured: Harry

However Ms Patel’s approval of the extradition of Mr Lynch has exposed an imbalance in the US-UK extradition arrangements. Former Brexit Secretary Mr Davis is furious that Ms Patel allowed the billionaire to be extradited to face criminal charges in the US before a separate civil fraud case against him in London’s High Court reaches its conclusion.

Mr Lynch, who built his software company Autonomy into a FTSE 100 heavyweight before it was sold to Hewlett-Packard in 2011 for £8.3 billion, handed himself over to police last week and was released on £10 million bail. He is accused of fraudulently inflating the value of Autonomy before it was sold to HP, making him a fortune.

He denies the allegations and claims the American firm botched the takeover.

His lawyers have argued that the case should be heard in British courts, not in America, because Mr Lynch is a British citizen who ran a British company listed on the London Stock Exchange which was governed by English law and UK accounting standards.

Mr Lynch’s local MP, Greg Hands, went with Mr Davis to meet Ms Patel at the end of last month and pleaded with her to wait until the conclusion of the High Court trial.

Writing in today’s Mail on Sunday, Mr Davis accuses Ms Patel of ‘spiriting’ Mr Lynch away to America before the verdict and says the decision shows how the extradition treaty is skewed too heavily in favour of America, while doing little to protect Britons.

‘When the US Department of Justice requests the extradition of a UK citizen, we effectively have no choice but to cough them up,’ he writes.

But when UK authorities want to extradite an American ‘the US Secretary of State “may” process the request. What the US “may” choose to do was made crystal clear in the recent case of Anne Sacoolas and the death of Harry Dunn’.

Mrs Sacoolas’s lawyers did not respond to requests for comment last night.

DAVID DAVIS: Thanks to Tony Blair's deeply unjust treaty, it's one rule for Americans and another for Britons

By David Davies for the Mail On Sunday

It has been just over a week since we re-established our status as an independent, sovereign nation, pursuing our own way in the world.

And yet, in Westminster Magistrates Court last week, we saw a vivid example of Britain already surrendering its sovereignty, this time over its justice system, with the formal arrest of Dr Mike Lynch for potential extradition to America.

Dr Lynch is one of this country’s most successful entrepreneurs. He founded an innovative British company, Autonomy, which in 2011 was bought by Hewlett-Packard. Now American prosecutors are claiming that he should be tried in America on charges about the way he ran that company, and how it was sold to HP, which has accused him of fraud.

But British justice is in motion. The Serious Fraud Office investigated the allegations against him and decided that there was no case for prosecution in 2015.

In Westminster Magistrates Court last week, we saw a vivid example of Britain already surrendering its sovereignty, this time over its justice system, with the formal arrest of Dr Mike Lynch (pictured) for potential extradition to America, writes DAVID DAVIES

HP also brought a civil case against Dr Lynch in the English High Court. It has just concluded after ten months of exhaustive testimony and the judge will rule in due course. That case reviewed millions of documents and heard dozens of witnesses in open court.

Dr Lynch himself was on the witness stand for more than a month, one of the longest cross-examinations on record.

There can be no doubt that Dr Lynch has faced justice in the UK, and that whatever the outcome, our system is working.

Yet before the judge can deliver a verdict, the Home Secretary has certified that Dr Lynch should be spirited away to America.

The fact that he was arrested at all brings into sharp relief the problems with our relationship with the United States. When the US Department of Justice requests the extradition of a UK citizen, we effectively have no choice but to cough them up. The UK-US extradition treaty of 2003 says that the Home Secretary ‘must’ process the request.

For the UK to extradite from the US, we have to clear a higher burden of demonstrating ‘probable cause’, which – unlike in the UK – can be challenged in the courts. After that, the US Secretary of State ‘may’ process the request. What the US ‘may’ choose to do was made crystal clear in the recent case of Anne Sacoolas and the death of Harry Dunn (pictured), writes DAVID DAVIES

The US prosecutors have no requirement to prove their case beyond stating ‘reasonable suspicion’, and there is no prima facie consideration of the charges in the UK.

Conversely, for the UK to extradite from the US, we have to clear a higher burden of demonstrating ‘probable cause’, which – unlike in the UK – can be challenged in the courts. After that, the US Secretary of State ‘may’ process the request.

What the US ‘may’ choose to do was made crystal clear in the recent case of Anne Sacoolas and the death of Harry Dunn.

The US-UK extradition treaty is a bad treaty. It was negotiated in secret by Tony Blair’s Labour Government, debated in haste and enacted unilaterally by Blair over strenuous objections from all sides of the Houses of Parliament. Its rapid passage was intended to enable the fast-track processing of potential terrorists after 9/11, yet that is not how it has been used.

The US-UK extradition treaty is a bad treaty. It was negotiated in secret by Tony Blair’s Labour Government, writes DAVID DAVIES. Pictured: Blair earlier this week

The proof of the imbalance is in the numbers. Since 2007, the UK has surrendered 135 UK nationals to the US, 99 of which were for non-violent crimes. During the same period the US has surrendered only 11 to Britain. This cannot be the outcome of a fair system being properly applied.

Dr Lynch now faces the prospect of adding to these grim statistics. In his case, the alleged conduct all took place in the UK, under UK law. We are now looking at the bizarre prospect that a UK citizen could be tried and potentially acquitted by an English judge, where the burden of proof against him is lower, but find himself in a US prison facing a charge where the burden is higher, before the UK case has even been decided.

Why would we give the US justice system priority over our own?

Should Dr Lynch be extradited and denied bail, as most foreign suspects are, he will face appalling conditions that are much worse than anything found in the UK. He will likely find himself in a high-security prison in a cramped cell with gang members, drug dealers and murderers.

And by potentially selling him down that river, we will be sending him to a place where 97 per cent of cases are settled by plea bargains.

People who have previously been extradited to the US have been told that if they pleaded not guilty, they would be denied bail and get 35 years in a high-security US prison, but if they pleaded guilty, they would get only three years, possibly serving some of it in a British jail.

Prosecutors will use this practice to try to convince Dr Lynch to admit guilt to a lesser charge. If he refuses, he will face the prospect of a deliberately intimidating lengthy sentence, and the costs of the trial could run into millions.

Dr Lynch is right to resist extradition. He is standing up for all of us against this unfair system.

It will send a chill wind through ‘global Britain’ if all UK businesses are effectively forced to comply with US laws and standards, and subject to US prosecution if they do not.

It would cripple the City and Britain’s ability to determine its own future.

That is why we need to look again at our extradition arrangements. They affect our ability to set and enforce our own laws.

We need to ensure our arrangements are fair, balanced and based on reciprocity. We need to give British citizens, including our businessmen and entrepreneurs, the protection, certainty and justice that they deserve.