People who report motorcycles that ride on city pavements or are parked illegally can receive rewards from next month as part of City Hall's clean-up campaign.
Anyone who provides photos, videos and the registration plate number of those who flaunt the law to their local district offices will receive half of whatever the perpetrator is fined, officials said.
The move aims to make up for the shortage of tessakit officers (city inspectors) overseeing public spaces in the capital.
The plan, which is expected to become law in the next few weeks, comes as city officials are struggling to regulate vendors of street food and other goods in tourist-heavy areas on Yaowarat Road and Khao San Road.
While more talks are needed to finalise the fate of the street vendors in these hot spots, Bangkok deputy governor Amnoy Nimmano said yesterday the city is authorised by law to use incentives, along with legal measures, against rogue riders and motorists who also inconvenience the public.
The 1992 Maintenance of Public Sanitary and Order Act imposes a maximum fine of 5,000 baht on violators and grants the informer half of this sum.
Pol Lt Gen Amnoy said the city has never enforced this rule in the past but a panel now has been set up to draft an ordinance to help clear up the city's streets.
It should be enforced by next month, he said.
City officials will locate violators by working closely with the Land Transport Department, which has a database of registered motorists, the senior policeman added.
If they fail to pay the fine within the specified time, "the city will take action", Pol Lt Gen Amnoy said.
As for recent attempts to regulate street vending in Bangkok, particularly on Yaowarat and Khao San roads, the government merely wants to improve their quality by focusing on "cleanliness and reasonable prices", Bangkok governor Aswin Kwanmuang said.
A roadmap for new regulations will become clearer after talks are held with Tourism and Sports Minister Kobkarn Wattanavrangkul, he said.
The talks will touch on various issues including operating hours and traffic conditions in certain areas, even the colour of vendors' aprons, he added.
In Thailand, colours like yellow and red have political connotations.
"This is an age of reconciliation," Pol Gen Aswin said. "I recommend they wear green because that's the official colour of City Hall."
Yaowarat, famous for its Chinese communities, and Khao San, well-loved by backpackers, are among a number of roads where the authorities organise cultural and other events.
But the governor stressed that Bangkok's plan to ban street food in other parts of the city still holds true.
Vendors will still be allowed to operate near city landmarks as long as they do not inconvenience local businesses, he said. Clearer regulations for Yaowarat and Khao San are expected in one month.