Try enforcing the laws inside the Sois as well. I've never seen a traffic cop inside a soi. Seems the sois are governed by the residents of the sois as they deem convenient for them, with cars and motorcycles parked in any available gap on the street. 3 passengers on Motorcycles none wearing a helmet.
Lately I have observed that the traffic cops are nowhere to be seen even on the roads let alone the sois.