The defence team of the two Myanmar nationals given the death sentence by the Supreme Court over the September 2014 murder of two British backpackers on Koh Tao were considering seeking a royal pardon for the pair on Thursday.
Nakhon Chompuchat said after the court's ruling that under law, a defendant facing the death penalty is required to lodge a petition seeking a royal pardon within 60 days if the case is being finalised.
"I am studying details of the court's ruling before seeking a royal pardon,'' Mr Nakhon said.
The court yesterday upheld the death sentences passed by the Criminal and Appeal courts for Zaw Lin and Wai Phyo, who is also known as Win Zaw Htun. Both were 22 years old at the time of their arrest.
The pair were convicted and sentenced for the rape and murder of Hannah Witheridge, 23, from Norfolk, and the murder of David Miller, 24, from Jersey, England on Koh Tao, in the Gulf of Thailand, on Sept 15, 2014.
They were also convicted of the theft of an iPhone from one of the victims.
The phone was found discarded near a hotel on the island by police and used as evidence against them. Two judges took turns in reading the court's ruling.
The highest court ruled that all the evidence, including DNA samples and witness statements, proved their guilt.
The court rejected the argument the police had fabricated evidence and arrested them as scapegoats.
The lawyers of the two defendants argued against the reliability of forensic evidence and the legality of the investigation process.
Lawyers for the two convicted men had claimed the evidence in the case was mishandled and that they made confessions under duress which they later retracted leading to questions about police competence and the judicial system in Thailand.
However, in its ruling, the Supreme Court said the investigators had solid forensic evidence against the defendants and their collection and handling of evidence including DNA samples was properly carried out.
The defendants were questioned but not charged until police had evidence to implicate them in the crime, according to the court.
The court dismissed allegations of mistreatment and mishandling of evidence, saying the forensic work was handled by respectable institutions and that there was no proof they were tortured.
The convicted defendants, dressed in light brown prison attire, have been held at Bang Kwang Prison in Nonthaburi since their conviction.
They were taken from this maximum-security prison to Nonthaburi Provincial Court, near the prison, to hear the final ruling on Thurday.
