This study analyzed the impact of road traffic signal violation detection on vehicle speeds in an urban setting. Data was collected and analyzed to establish a vehicle speed probability density model before, within, and after the road traffic violation detection area. Results showed that the average and maximum speeds within the traffic violation detection area were significantly lower than those before and after it. Speeding vehicles were reduced from 70.1% to 15.9% when passing through the traffic signal violation detection had a limited effect in regulating driving behaviors and reducing speeding, but it was effective in the vicinity of the traffic signal violation detection system.