Two Myanmar migrant workers sentenced to death for the murder of two British backpackers on a Thai holiday island will learn their fate Thursday when the verdict on their final appeal is delivered.
Zaw Lin and Win Zaw Tun were found guilty of the rape and murder of Hannah Witheridge, 23, and of killing David Miller, 24.
The pair's battered bodies were found on a beach on the southern diving resort of Koh Tao in September 2014.
Prosecutors insisted the evidence against the men from Myanmar's impoverished Rakhine state was clear, and a lower court upheld their conviction in 2017.
But during the proceedings, the defence said authorities mishandled the investigation and DNA evidence, not allowing independent analysis of samples and using confessions the pair said were coerced.
Police were accused of buckling to pressure to solve a crime that made global headlines and threatened to damage a tourism sector that accounts for a fifth of Thailand's economy.
Zaw Lin and Win Zaw Tun arrived at the court Thursday morning on the outskirts of Bangkok in tan prison jumpsuits.
Andy Hall, an international adviser to the defence, said the evidence against them was "unreliable".
"The death penalty sentence against the two accused and their conviction should be reversed and quashed."
Thailand's legal system is notoriously opaque, with some cases flying through the courts while others take years.
The 2017 appeal decision was presented to the two men with no translator and without lawyers present, according to the defence.
If the Supreme Court's verdict on Thursday upholds the ruling their last hope is the possibility of a royal pardon.
Last year Thailand carried out its first execution since 2009, a sudden resumption of the death penalty that was condemned by rights groups who hoped the country was moving towards abolishing the practice.
The verdicts on the 2014 double killing divided relatives.
Miller's parents backed the court's conviction, but Witheridge's family were more cautious in drawing conclusions while her sister Laura later called the investigation "bungled".