Thai authorities have convicted two bar workers for the murders of the British backpackers, amid allegations that the suspects made confessions under duress.
Mr Miller and Miss Witheridge were brutally murdered on the holiday island of Koh Tao in September.
Zaw Lin and Wai Phyo have been sentenced to death.
Thai authorities have banned beach parties on some of the country's most popular islands as part of a security clampdown after Jerseyman David Miller and fellow tourist Hannah Witheridge were murdered on the paradise island of Koh Tao.
Authorities say the ban is aimed at tackling crime and negative publicity as the country's tourist season reaches its peak.
Chatpong Chatputhi, Governor of Surat Thani province which includes Koh Tao, said all beach parties would be banned with the exception of the Full Moon Party on Phangan island.
David Miller from Jersey, and Hannah Witheridge from Norfolk were found dead on a beach in Thailand in September 2014.
The Miller have told ITV News they are against the death penalty issued to the two men convicted of David's murder. The pair are appealing.
A human rights activist defending the men found guilty of murdering David Miller says the 'botched' investigation can't prove their guilt.