Koh Tao murders

On 15 September 2014, the bodies of Hannah Witheridge, 23, from Hemsby, England, and David Miller, 24, from Jersey, were found on Sairee Beach on the Thai island of Koh Tao between 4 and 5 am, a few hours after their deaths. Both had been struck several times on the head; Witheridge had been raped, and Miller had drowned. The pair, both backpacking students, had met at their hotel and were last seen leaving a beach party together after 1 am. A bloody hoe believed to be the murder weapon, a wooden club, cigarette butts, and a used condom were found near the bodies.

The police investigation, conducted under pressure to produce quick results due to concerns about tourism, initially named several unfounded suspects, including a British tourist who was the subject of a nationwide manhunt before the lead was dropped. Two weeks after the murders, two 22-year-old illegal Burmese migrant workers, Zaw Lin and Wai Phyo, were identified via CCTV footage and arrested. Following interrogation using Burmese food vendors as interpreters, the men confessed, but later retracted their statements, alleging torture, threats, and coercion. The national police chief denied torture occurred. Thailand's National Human Rights Commission attempted to investigate the allegations, but police representatives did not appear at scheduled meetings.

The two men were indicted on charges including premeditated murder, killing to conceal a criminal offence, rape, and illegal entry into Thailand. An 18-day trial began in July 2015 at the Koh Samui Provincial Court. The prosecution relied heavily on DNA evidence linking the men to samples from Witheridge's body and the murder weapon. The defence argued the investigation was flawed, citing mishandled forensic evidence, lack of legal representation during interrogation, and scapegoating of vulnerable migrant workers. A court-ordered DNA retest of the murder weapon reportedly did not match the defendants, though the case proceeded on other DNA findings. On 24 December 2015, Zaw Lin and Wai Phyo were convicted of murder and sentenced to death; Wai Phyo was also convicted of theft.

Appeals to the High Court in 2017 failed, and the Supreme Court of Thailand upheld the convictions in August 2019, stating the forensic evidence was "clear, credible, and detailed." On 14 August 2020, a royal decree issued by King Vajiralongkorn commuted the death sentences to life imprisonment, a decision acknowledged by Miller's family.

The case drew widespread criticism from Amnesty International, Human Rights Watch, the International Commission of Jurists, and Thailand's own National Human Rights Commission, which raised concerns about torture allegations, inadequate legal representation, translation issues, and contamination of the crime scene. The guilty verdict prompted protests in Myanmar and cyberattacks on Thai police and court systems attributed to the hacker group Anonymous. Thailand's government, concerned about effects on tourism, increased policing on the island, though the murders had little lasting impact on visitor numbers to Koh Tao.