Koh Tao Murders: Court Says DNA Trumps Other Flaws in Case

Sue Miller holds photograph of her son, David Miller, during a Dec. 24 news conference at Samui courthouse.

SAMUI — Although it accepts that the case against the two Myanmar men – found guilty of killing two British tourists in southern Thailand last year – was not without flaws, the court said yesterday that DNA samples collected from the crime scene are so incontrovertible, that they justify a conviction.

The flaws include lack of chain of custody in evidence, arrest and interrogation of the two suspects without charge or legal representation and a lack of any witness who saw the two defendants committing the crimes.

Zaw Lin and Wai Phyo, both 22, were found guilty Thursday of killing British backpackers David Miller and Hannah Witheridge on Koh Tao on Sept. 15, 2014. The two men were also convicted of raping Witheridge before killing her. Both victims died in the early hours of Sept. 15.


For their alleged crimes, the court on Samui island yesterday morning sentenced both defendants to death – the highest penalty for premeditated murder.

Zaw Lin and Wai Phyo, who worked as bar workers on Koh Tao, were arrested on Oct. 1 2014 and brought to a police “safehouse” on the island for interrogation. They were not formally charged until Oct. 3 2014.

The pair initially confessed to the crimes, but later retracted their statement after receiving legal counsel from a team of pro-bono lawyers. The two men said they were coerced by police into making the false confession.

Police said DNA samples collected from the crime scene and from Witheridge’s body identified Zaw Lin and Wai Phyo as the murderers, a point contested by the defense team, who argued that the DNA test was conducted behind closed doors by several police officers without proper documentation.

Siding with the prosecutor, the court yesterday accepted the DNA test as valid and up to international standards. It rejected argument from the defense lawyers that the DNA test was performed solely by the Institute of Forensic Medicine, which operates under the Thai police force, could have been forged or tampered with.

According to the court, the test was so well documented and photographed that a forgery could not possibly have occurred.

The evidence

For the court, the most significant evidence that ties Zaw Lin and Wai Phyo to the crime is traces  of their DNA found on Witheridge’s body. Her body clearly showed signs of rape, the court said.  

While the murder weapon – a garden hoe – did not contain DNA traces of either men, it is reasonable to conclude that  both Witheridge and Miller were killed by the rapists to cover up their initial crime, the court said.

Furthermore, traces of Wai Phyo’s DNA were found on a cigarette stub left on Sai Ree Beach, along with DNA that belonged to a third Myanmar man called Mau Mau. Mau Mau, 23, told police he was playing guitar with Zaw Lin and Wai Phyo several hours before the murder took place.

The two men admitted in the trial that they were playing guitar and drinking beer, whilst sitting on a log. However, they insisted that they left the beach before the killings took place and went swimming in the sea on their way home instead.

The validity of the DNA test by the police was among the most contentious issues during the trial, which lasted from July to October. Defense lawyers argued that the test was not independently conducted, and requested that the remnants of DNA samples be retested by the Central Institute of Forensic Science, which operates under the Ministry of Justice.

However, the defense team eventually abandoned the idea of the retest, saying they were unsure whether the DNA remnants would still make for an accurate retest.  

Another key item that implicated Zaw Lin and Wai Phyo, the court said, was Miller’s cell phone that went missing from the crime scene and was later found at Wai Phyo’s residence. Wai Phyo said he found the phone on the way back to his home – an argument the court rejected as implausible.


Other key points in the verdict:

No direct witness implicated the two defendants at the crime scene, but the absence of such witnesses is understandable because the crime took place in the dead of the night, in a secluded area that is sparsely populated.

Smashed phone found at second defendant’s home was proven to belong to Miller, with help from Miller’s father to identify the IMEI serial number. The second defendant claimed he found the phone on the way back to his residence, but this claim is deemed questionable.

Witnesses said they saw Mau Mau and two other men playing guitar on a log on the beach close to the crime scene. The two defendants argue it was too dark to see the crime scene, but the pair had been sitting long enough to adjust their eyes to the darkness.

The two defendants failed to produce any alibi to confirm their whereabouts after they left the log and parted company with Mau Mau.

CCTV footage indicates that Miller and Witheridge left AC Bar, where they were drinking prior to their deaths, by the back door, which led directly to Sai Ree Beach. The path between AC Bar’s back door and the crime scene also goes past the log where the two defendants were allegedly drinking beer and playing guitar.

The two defendants said they suddenly had the idea of going swimming in the sea on their way back to the residence. It was in the dead of the night, and it was raining slightly. It is unimaginable that any person would have made this decision, unless they wanted to erase the evidence on their shirts and bodies.

The garden hoe did not contain traces of DNA of either men. This lack of DNA could be explained by several factors. For example: the perpetrators' hands might be dry or the item might have been washed in the sea.  


‘No previous grudge’

The court also acknowledged in its verdict that the prosecutor’s case against the two men is marked by several irregularities and shortcomings: namely, a lack of “chain of custody”, a paper trail that marked the transfer of documents and evidence up the ranks in the police force.

Throughout the trial, the defense lawyers argued the lack of chain of custody meant crucial evidence, such as the DNA test result, could have been easily forged.

This concern was brushed aside in the court verdict; the judges said each police agency has its own form of chain of custody.

Another point of contention was the fact that the two suspects were arrested and interrogated without proper legal counsel and interpretation.

The interpreter provided by police for Zaw Lin and Wai Phyo later turned out to be a roti vendor, from Myanmar.

Most importantly, the defense lawyers argued, the two defendants said they were beaten, tortured and threatened by police to make the false confession, therefore rendering their arrests and interrogation unlawful.

However, the court dismissed these objections. The two men admitted they had some “passable” conversation with the interpreter, so the interpreter was qualified enough for the job, the court said.

The court also believes police had reasonable grounds to arrest the two defendants without charges. When first questioned by police, the two defendants failed to show their passport or ID to police, which was a sufficient ground for “offense in plain sight” that allows police to arrest them for further interrogation, the court said.

When a lawyer was finally provided by the police for the two defendants, it was not the lawyer requested by by the two men, the court acknowledged. But the court then argued that lawyer is certified by Lawyer Council of Thailand, and therefore eligible to represent the two men during interrogation.

“This is a departure from rules rather than from laws,” the verdict read.

As for the claim of torture, the court noted that the doctor who inspected their condition in police custody said no clear sign of beating or torture was found.

Also repeatedly mentioned by the court throughout the verdict is the argument that law enforcement officials involved in this investigation “have not previously known the two defendants and have no previous history of personal grudge or disputes with the two defendants,” so it was unlikely that these officials would conspire against the two Myanmar men.

Defense team still hopeful

Nakhon Chompuchat, head of the defense team, said he respected the court verdict, but expressed his disappointment that he could not convince the judges to see “reasonable doubt” in the case.

“The court said it was beyond reasonable doubt, but to us there are still some doubts,” Nakhon told reporters outside the courthouse yesterday.

Nakhon cited the example of the lack of chain of custody that would have verified DNA tests on Zaw Lin and Wai Phyo; he said the prosecutor told him the documents did exist, but simply chose not to show them to him.

The lawyer also regretted that the court would not hear his concern about the alleged police torture of his clients.

Nevertheless, he said he’s still confident that his team will be able to persuade the upper courts to dismiss the charge against Zaw Lin and Wai Phyo.

The lawyers team is expected to file an appeal in the next 30 days. In the meantime, Zaw Lin and Wai Phyo will be moved to death row at a prison in Nakhon Si Thammarat province, lawyer Nakhon said.

There won’t be any new evidence or witness in the Appeal Court; Nakhon explained; the appeal trial would be mostly an “interpretation” of existing evidence.   




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