Harry Dunn’s parents have said they feel “really proud of ourselves” for bringing a judicial review into the immunity granted to his alleged killer.
Mr Dunn, 19, died when his motorbike was in a crash with a car near RAF Croughton, Northamptonshire, in 2019.
The suspect, Anne Sacoolas, later flew to the United States citing diplomatic immunity.
She was charged with causing death by dangerous driving in December but an extradition request was denied.
Mrs Sacoolas, 43, whose husband Jonathan worked as a technical assistant at the base, was allegedly driving on the wrong side of the road when she hit Mr Dunn.
His parents claim the Foreign, Commonwealth and Development Office (FCDO) wrongly decided Mrs Sacoolas had diplomatic immunity and unlawfully obstructed Northamptonshire Police’s investigation.
Mr Dunn’s mother, Charlotte Charles, said after the hearing at the High Court: “We have to wait for possibly a few weeks for the outcome. But it’s done, it’s dusted.
“We feel really proud of ourselves for having brought this judicial review.
“I just feel as a family, as parents, we couldn’t be more proud that Harry’s given us the strength to do it.”
Tim Dunn, Harry’s father said: “I thought the last two days were very informative… but it’s just a shame that Harry had to die for us to get where we are today.
“Fingers crossed it goes our way when they announce their decision.”
At the High Court, Lord Justice Flaux, sitting with Mr Justice Saini, said they would hand down their judgment “as soon as we possibly can”.