Mr Miller’s family, who live in St Helier, took the step in an effort to prove that their son’s phone was in the possession of one of the Burmese men accused of killing him on the night that he died.
The move comes as the court in Koh Samui, Thailand, announced that it would not deliver its verdict until Christmas Eve.
Judges at the court in Koh Samui set the date to deliver their verdict after the 20-day trial concluded yesterday with evidence from defendants Zaw Lin and Wai Phyo.
Sky News have reported that Mr Miller’s family secured the IMEI number and passed it to the Thai Embassy.
British investigators flew to Thailand last year to oversee the investigation but did not formally get involved with the case because there is the potential that the defendants could face the death penalty.
The prosecution have said that British authorities had previously confirmed that the phone belonged to Mr Miller, but only verbally.
However, a defence witness has said that that was not true.
Defendant Wai Phyo, 22, has never denied finding a phone on the beach on the night of the murders.
He said he picked it out of the sand some distance from the murder scene and took it home, but could access it because he did not know the phone’s security code.
‘The next day we heard about the murders and we were worried it might belong to someone involved,’ Wai Phyo told the court on Sunday.
‘My friend smashed up the phone and threw it into the undergrowth behind our hut.’
The bodies of Mr Miller (24), a former Victoria College student, and Hannah Witheridge (23), who was from Norfolk, were found on Sairee Beach on the island of Koh Tao last September.
The prosecution claims that DNA evidence places both the accused at the scene of the crime and proves that they are responsible for raping Miss Witheridge and bludgeoning both victims to death.
But the defence has called a series of witnesses to discredit the DNA evidence, including the head of Thailand’s Central Institute of Forensic Science.
In his final testimony, Wai Phyo repeatedly said he was innocent, and claimed that he had been sexually, physically and psychologically abused to make him confess to the crimes.
He added that he had been kicked, punched, slapped and threatened with dismemberment, electrocution and death.
The defendants face charges of murder, rape and robbery. If found guilty they could face death by injection.
David Miller
‘Dangerous’ or ‘Disco’ Dave to his friends, former Victoria College student David Miller was described as ‘a trusted friend’ by his brother Michael at the funeral, which was attended by hundreds of people at Trinity Church in October. The ‘blooming blue-eyed’ Islander, who was a talented artist, had been travelling in Asia with friends after spending the summer working in Australia. Mr Miller began his trip after graduating from a Leeds University Master’s-level civil engineering course. After his death, scores of friends and relatives paid tribute to the ‘one of a kind’ who was known for his humorous and friendly personality.
Hannah Witheridge
The gifted student (23) had travelled to Koh Tao with three friends. It is believed that she met Mr Miller on the island.
She had recently completed a BA in education studies at the University of East Anglia in Norwich, graduating in 2012 before moving to Colchester to study for an MA in speech therapy.
12 September 2014: David Miller, Hannah Witheridge and friends arrive at Koh Tao separately. They are staying at the Ocean View Bungalows, Sairee Beach.
14 – 15 September (early morning): Mr Miller and Miss Witheridge are captured on CCTV at Choppers Bar and then entering separately the AC Bar near Sairee Beach. Zaw Lin and Wai Phyo and a friend are seen on CCTV buying cigarettes on Sairee Beach, close to where the victims’ bodies were found.
15 September: The bodies are discovered near rocks on Sairee Beach close to Ocean View Bungalows. Post-mortem examinations carried out at a later date reveal that Mr Miller was killed by blows to the head and drowning, while Miss Witheridge died from head injuries and may have been raped.
15 September to 2 October: Investigations are carried out as Koh Tao becomes a hot-bed of international media. Police say DNA recovered from cigarettes found near the bodies and on Miss Witheridge will be crucial to finding those responsible. DNA samples are subsequently taken from hundreds of people at Koh Tao.
Jersey brothers Christopher and James Ware, who had been sharing a room with Mr Miller in Koh Tao, voluntarily stay in Thailand to help the police with their inquires.
2 October: Zaw Lin and Wai Phyo are arrested. Zaw Lin is apprehended at Koh Tao and Wai Phyo at a ferry terminal in Muang district in the Surat Thani province on the mainland. Police then reveal that both men have confessed to the murders and that DNA evidence links them to the crime scene and DNA found on Miss Witheridge’s body.
3 October: Zaw Lin and Wai Phyo are made to publicly re-enact the alleged crime on Sairee Beach. The re-enactment is observed by the international media.
7 October: The National Human Rights Commission of Thailand visit Zaw Lin and Wai Phyo in Koh Samui prison. They report to the media that the defendants both confessed to the crimes because they had been tortured, reportedly by being given electric shocks.
14 October: Koh Samui Court holds a preliminary witness hearing for three Burmese prosecution witnesses. They testify that the defendants were on Sairee Beach the night of the murder and Wai Phyo had found a mobile phone which may have belonged to Mr Miller but had passed it onto his unidentified friend.
October 20 to 23: The UK Foreign Office announce that British detectives will travel to Thailand to oversee the investigation following an intervention from Prime Minister David Cameron as controversy surrounding the Thai police’s handling of the case grows.
21 October: Zaw Lin and Wai Phyo retract their confessions to lawyers. Both allege they were beaten and tortured into confessing.
6 November: The defendants formally retract their confessions to case investigators.
8 December: The pair are charged at Koh Samui Court with murder, rape, illegally entering the country and residing without documentation. They deny all the charges.
26 December: During a preliminary case hearing at Koh Samui Court, the prosecution and defence agree to an 18-day trial starting on 8 July.
22 to 30 April 2015: Defence submit a formal request for independent testing of the DNA profiles of the two accused. The presiding court judge indicates to the lawyers that he would consider ordering the re-examination of forensic evidence.
