If you have got caught up in a scam in Bangkok it is VERY important that you report it. If you don’t, then it is as if it never happened. If everyone reports these scams to the police then we will come one step closer to eradicating scams across Bangkok. There is nothing the police can do other than charge these people with loitering. However, if you make an official complaint at the local police station then there is a real chance criminal charges will be brought up against these scammers. For example, they can be charged with extortion.
If you cannot speak Thai then it may sometimes be difficult to not only find out where the local police station is located, but also difficult to communicate with the police who may not speak any English. So, what you should do is contact the Tourist Police first. If you cannot find any nearby, then you can call them for free on their hotline: 1155. When I was trying to report a scam the local Tourist Police weren’t very helpful at first. But, I persisted and they eventually called this mobile unit that took me to the local police station to file a report.