The collision between a bus carrying primary school students and teachers and a dump truck, which is not allowed to enter the downtown during the day, that left one student dead, one critically injured, and several others injured in Nantong, Jiangsu province, on Friday morning, raises questions on the responsibility of the authorities that are in charge of maintaining traffic lights. A black-out of the red traffic light that should have halted the bus driver is believed to led to the accident.

Some media reports quoted local residents as saying the traffic light had been malfunctioning for days. That begs the questions: For how long exactly and why had it not been fixed?

According to the Road Traffic Safety Law, if traffic lights, signs and road markings are damaged or missing, the department managing roads and traffic facilities is expected to set up warning signs and repair them promptly. If the traffic management department of the police discovers situations that endanger traffic safety and no warning signs have been put up, it is expected to divert traffic and notify the responsible department. Not doing so amounts to dereliction of duty.

In an earlier case where two vehicles collided because two complementary traffic lights were green simultaneously, a court held the signal light management department liable for compensation. In the Nantong case, the probe will decide if the signal light management department should bear legal responsibility.