Two Burmese migrants accused of murdering a pair of British backpackers in Thailand should be acquitted because of the "unreliable" evidence in the case, a court has heard.
Hannah Witheridge, 23, from Hembsy, Norfolk, and David Miller, 24, from Jersey, were found dead on the island of Koh Tao on September 15 last year.
Burmese migrants Zaw Lin and Wai Phyo have been on trial for murder after denying their involvement.
Both defendants, aged 22, initially confessed to the killings but later retracted these statements, telling the court they had been tortured. Police have denied they tortured the accused.
In a closing statement to Koh Samui Court, the legal team representing Lin and Phyo said the pair were questioned by police "without lawyers or trusted persons present", while DNA samples were taken from them "involuntarily".
The statement said: "The accused's original confessions cited by the prosecution in court came about involuntarily from torture or abuse that made them fear for their lives and safety in the context of a wider case investigation when migrants reported systematic abuse on Koh Tao Island.
"These written confessions, even if they had been signed, shouldn't be considered by the court."
The defendants' lawyers said re-enactments of the murders were "staged under threat of violence," while DNA samples from the alleged murder weapon - a garden hoe - did not match the DNA profiles of the accused.
They added: "The DNA evidence allegedly matching the accused as well as all surrounding or circumstantial evidence in this case apparently showing the guilt of the accused is unreliable and should be inadmissible and not considered by the court.
"The prosecution case is marked by an absence of significant evidence needed to prove the guilt of the accused for crimes they are charged with."
Post-mortem examinations showed that the young backpackers, who had met on the island while staying at the same hotel, both suffered severe head wounds and that Miss Witheridge had been raped.
The court is expected to deliver its verdict in the trial on December 24.