LONDON — Britain and the United States have agreed to end a legal loophole that allowed an American woman to flee Britain after she was involved in a car accident that killed a teenager, the British authorities said on Tuesday, almost a year after the crash started a diplomatic tug of war between the two countries and sparked widespread outrage in Britain.
The woman, Anne Sacoolas, the wife of an American diplomat, fled Britain under diplomatic immunity weeks after her car collided with the motorcycle of Harry Dunn, 19, near Royal Air Force Croughton, a military base operated by the U.S. Air Force in central England.
For nearly a year, Mr. Dunn’s parents, Charlotte Charles and Tim Dunn, have campaigned to have Ms. Sacoolas prosecuted in Britain, going to the White House in October, where President Trump welcomed them and tried to arrange a meeting with Ms. Sacoolas, who he said was waiting in a room nearby. Mr. Dunn’s parents refused to meet her.
The police in Britain have said that Ms. Sacoolas was driving her car on the wrong side of the road in Brackley, a town near the base and about 60 miles northwest of London, at the time of the crash in August.
The case put a focus on special diplomatic arrangements affecting Americans who worked at the base and their families.
Under the United Nations’ Vienna convention on diplomatic relations, members of diplomatic staff and their families positioned in a foreign country are entitled to immunity. An arrangement between the U.S. and Britain recognized the Americans working at Croughton as embassy staff, but waived this immunity.
However, that waiver did not cover the families of the employees. So, while American personnel at the base could not claim immunity in the event of a crime committed outside their duties, their family members could.
That is no longer the case.
Foreign Secretary Dominic Raab said on Wednesday that all American staff members at the Croughton military base would now be subject to the same rules.
The changes, which came into effect on Monday but were made public on Wednesday, came a day after Secretary of State Michael Pompeo met with Prime Minister Boris Johnson in Britain. Mr. Johnson’s office said he had raised the issue of Ms. Sacoolas with Mr. Pompeo.
The waiver arrangement had been restricted to the base, and the changes will not affect broader agreements on immunity for diplomatic staff. American personnel and their families posted elsewhere in Britain will continue to enjoy diplomatic immunity.
“We have the deepest sympathy for Harry Dunn’s family,” Mr. Raab said in the statement. “No family should have to experience what they have gone through and I recognize that these changes will not bring Harry back.”
In a written statement to Parliament, Mr. Raab said that the loophole “could not in future be used in the same way as in the tragic case of Harry Dunn.”
Mr. Dunn’s family welcomed the decision but said they would continue to press for Ms. Sacoolas to stand trial in Britain.
“We now need Dominic Raab to work with us to make sure that we get her back to the U.K. to face justice at some point soon,” Ms. Charles told the BBC. “We always live with hope that one day she might just decide of her own accord to put herself on a plane and come back over here. We definitely will keep the pressure up.”