The husband of the US woman granted diplomatic immunity after a car crash which killed a teenager was not registered as a diplomat, it has emerged.
Jonathan Sacoolas, whose 42-year-old wife Anne fled Britain after Harry Dunn's death in the smash, is not on the published list of accredited diplomats in the UK, a lawyer says.
The spy also worked at an intelligence base rather than a diplomatic mission, but both the US and UK governments have called him a diplomat.
Therefore, it seems Mr Sacoolas is not entitled to diplomatic immunity.
Mark Stephens, an international lawyer, said: "There is a treaty between the two governments."
"That treaty though doesn't bind Northamptonshire Police and it doesn't bind the family of this poor boy who was deceased, and as a consequence of that they can apply for her extradition to come back to face manslaughter charges."
The diplomatic immunity is granted by the Vienna Convention, which is enshrined in international law.
This has huge implications, and Sky News reports Foreign Office and police may have been wrong in allowing Mrs Sacoolas to leave the country after the crash.
Police believe it happened when Mrs Sacoolas pulled out on to the wrong side of the road as she emerged from Northamptonshire's RAF Croughton on 27 August.
The US Embassy said it "has nothing at this time" on the matter.
But yesterday Daily Mirror exclusively revealed Mrs Sacoolas was charged with "failure to pay full time and attention" for poor driving in November 2006 in Virginia.
She was fined £200 for being distracted behind the wheel near her home.
