Knowles said several personal items were found at the scene of the crash, but none were physically on a person.
These included a phone in a case and a driving licence in the name of Joshua Johnson, as well as a second phone displaying medical identification in the name of Trevor Wynn, with a bank card attached to the device.
Knowles said one of the attending officers used this to establish the next of kin and called Trevor’s mother to explain what had happened.
She provided her son’s college identification card plus a description of his appearance, build and footwear.
The ID card was then taken to the mortuary by the officer, Knowles said, where details of build and clothing were compared.
“The officer was satisfied that this was the body of Trevor Wynn,” he added.
Meanwhile, a second officer, who had been travelling in an ambulance with the surviving male, said he had been told by an officer at the scene the victim was Joshua Johnson, based on driving licence photos.
That officer then liaised with medical staff at the hospital and the photograph was compared with the victim.
The medical staff and officer were satisfied the person in hospital was Joshua Johnson, said Knowles, who had no involvement in the investigation prior to 5 January.
Doubts about identity emerged when the boy woke up on Sunday, prompting Johnson’s father to call South Yorkshire Police and voice concerns the person in hospital was not his son.
Knowles said at that point it was decided police would no longer rely on visual identification and obtained dental records, which confirmed the boy in hospital was actually Trevor.