Maybe it was helmet check day.
Do not leave your house in Thailand if you’re not wearing any underwear. If you're travelling to Thailand, make sure you pack enough underwear to last you for the entire trip. It is illegal to leave your house without wearing underwear in Thailand and, although I am not quite sure exactly how this law is enforced, I wouldn't want to take any chances.
3. Do not drive a car in Thailand if you’re not wearing a shirt. Don’t let the tropical weather tempt you to joy ride with your shirt off in Thailand. Police can will hand out tickets if they spot you topless while driving a car or motorcycle. Penalty is a mere slap on the wrist (or sun-burned shoulders). Tickets go for a few hundred baht or about $10.
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