A State Department spokesperson cited Sacoolas’ diplomatic status at the time of the accident and said granting such an extradition “would render the invocation of diplomatic immunity a practical nullity and would set an extraordinarily troubling precedent.
“The United States has a history of close law enforcement cooperation with the United Kingdom, and we value that relationship,” the spokesperson said. “The United States government again expresses its sincere condolences and sympathy to the Dunn family for the loss of their son.”
Dunn, 19, was killed August 27 in Croughton in central England, which is home to a Royal Air Force station controlled by the US Air Force. UK police say Dunn was riding a motorcycle when he was struck by a vehicle that was traveling on the wrong side of the road.
Sacoolas claimed diplomatic immunity and left the country in the aftermath of the incident. In October, Sacoolas’ attorney Amy Jeffress said officers had interviewed her in the UK twice before she claimed immunity.
“We express our deepest sympathies and offer condolences to the Dunn family for their loss. We will continue to look for options for moving forward. We are disappointed by today’s announcement and fear that it will not bring a resolution closer,” that State Department spokesperson said.
“This was a tragic accident, a young man has lost his life, and his family is grieving. No one could hear about this tragic accident and not feel incredible sadness over this loss.”
Sacoolas’ legal team did not offer a new comment on Thursday, instead referring CNN to a statement from attorney Amy Jeffress earlier in January, which said in part: “Anne is devastated by this tragic accident and would do anything she could to bring Harry back. She continues to grieve for Harry and his family.”
Jeffress has previously said that her client would not return voluntarily to the UK. “This was an accident, and a criminal prosecution with a potential penalty of 14 years imprisonment is simply not a proportionate response,” Jeffress said last month.
Radd Seiger, a spokesman for the Dunn family, said they wouldn’t “stand for it” in reaction to the decision to not extradite Sacoolas. He posted the comment to Twitter early Friday UK time.
“It happens in Europe, as the roads are opposite. It’s tough if you’re from the United States. You do make that right turn when you are supposed to make a left turn; the roads are opposite. She says that is what happened. That happens to a lot of people, by the way.”
This story has been updated with reaction to the news and background on the accident.
CNN’s Jackie Castillo, Tara John, Jack Guy, Lindsay Isaac, Doug Criss and Ivana Kottasová contributed to this report.