Although wearing black is not a crime in Thailand, a meeting chaired by the Police Chief on 26 July called on police around the country to monitor a movement to wear black on 28 July to mark the birthday celebrations of King Vajiralongkorn.
The decision was reportedly made in response to several Facebook posts calling on people to wear black for the King’s birthday on Thursday  .
During the meeting, the act was deemed to be ‘improper’ and police around the country were ordered to be cautious and monitor public activities. In cases of legal violations, police were also told to take a suspect's outfit colour into consideration.
In Thailand, wearing black is associated with paying respect to the dead. At funerals in the kingdom, people generally wear black or white clothing.
Following the death of King Rama IX, government officers and people around the kingdom dressed in black or attached black ribbons to their shirts to express their condolences.
Mourners with black outfits at Sanam Luang, where located the late King Rama IX crematorium. (File photo)
In contrast to these state-sponsored calls to wear black, the use of black for protest purposes has previously drawn the wrath of security officers.
On 24 October 2019, the public prosecutor filed charges against Wutthipong “Ko Tee” Kotthammakun, Chucheep “Uncle Sanam Luang” Cheewasut, Siam Theerawut, Kritsana Tupthai, Wat Wanlayangkoon and several others for their alleged involvement in the republican Thai Federation movement.
In total, some 21 people were prosecuted in 10 cases stemming from the group’s effort to change the system of government to a federation. Movement leaders called on people to fly banners along with a red-white Federation flag, and to wear black shirts bearing a red and white logo on 5 December, birthday of the former King. The campaign led to wide-scale arrests and police harassment
The Thai Federation shirt
Thai security officers identified 5 movement leaders: Wutthipong “Ko Tee” Kotthammakun, Chucheep “Uncle Sanam Luang” Cheewasut, Siam Theerawut, Kritsana Tupthai, and Wat Wanlayangkoon. All except Wat, who passed away in a third country in 2022, disappeared while in self-imposed exile.
The wearing of black shirts by federationists was one of many offences deemed by the prosecutor to be an act of sedition. In 2020, however, the Court dismissed the issue, stating that people are free to wear any colour they want, as long as there are no legal prohibitions against doing so.
In a separate incident on 24 October 2017, three uniformed soldiers and 11 plain clothes officers arrested Ekkachai Hongkangwan, a political activist and former lèse majesté convict, at his house.
The arrest came after Ekkachai posted on Facebook that he planned to wear a red shirt, an anti-establishment symbol, on the day of the late King’s cremation ceremony, a day when Thai people were expected to wear black.
Ekkachai was taken to Kanchanaburi and detained by police until the cremation funeral concluded.
During the same period, a number of activists with histories of monarchy-related protests came under police scrutiny.
Note: At 14.45 on 27 July 2022, Prachatai English replaced the report with an grammatically-edited version.