Judges at the court in Koh Samui were shown footage of Islander David Miller (24) and Hannah Witheridge (23) from Norfolk taken from security cameras just hours before their bodies were found near rocks on Sairee Beach in Koh Tao in September.
Burmese migrants Zaw Lin and Wai Phyo, both 22, are accused of killing Mr Miller and Miss Witheridge.
Their mothers, Daw Phyu Shwe Nu and Daw May Thein have travelled to Koh Samui to watch the trial.
Thai prosecutors and senior police officers claimed they had key forensic evidence linking the pair to the crime.
However, earlier this month the court was told conflicting reports by police witnesses who first said that some forensic evidence had been lost or ‘used up’.
The police then retracted that statement, saying DNA samples had not been lost.
The court later ordered that remaining, usable forensic evidence – including a garden hoe that police claim was the murder weapon – should be sent for re-examination at the Thai justice ministry’s central forensic institute.
This morning, before the court resumed, Nakhon Chompuchat, the lead defence lawyer, said his team’s questioning would focus on the DNA evidence.
‘We still have not seen any progress on the request to see the DNA gathered by police,’ he told a news agency.
Later today the court was expected to be shown CCTV footage of the defendants last movements as well as a man seen ‘running’ near the scene.
The defendants deny charges of murder, rape and robbery.
The case is due to resume tomorrow.
If found guilty the pair could face death by injection.
