British police faced a wall of silence when trying to get background information from their Saudi counterparts, according to a source close to the investigation into prince Saud Abdulaziz bin Nasser al Saud.
They were also confronted with embassy officials who tried to claim Saud had diplomatic status after he was arrested for killing Bandar Abdulaziz in February.
But although he does have the special status in some Middle Eastern countries, he does not have it in Britain, a check by police with the Foreign Office found.
Detectives knew nothing about the history of the defendant and his victim before they came to London apart from what Saud had told them.
They have no knowledge of whether the prince has a history of violence.
In addition, the owner of a Saudi-registered telephone that he spent hours communicating with around the time of the killing remains unknown.
Requests for information about the backgrounds of the prince and his servant, next of kin, telephones and sim cards were made through Interpol and received by authorities in the kingdom, said the source.
"You have to go through official channels. We have made our requests for information. There has been very little response.
"The only things we know about his life are since he's been in London."
A lawyer representing the victim's family travelled to the UK after the murder but there has been no contact between police and Mr Abdulaziz's relatives.Reuse content