Under what condition do your vehicle's lights not need to be kept on when parked on a public road?

The correct condition under which your vehicle's lights do not need to be kept on when parked on a public road is during daylight hours. During daylight, the visibility is typically sufficient for other drivers and pedestrians to navigate safely without additional light from parked vehicles. This assumption is based on the idea that natural light is adequate for visibility, thus reducing the necessity for parking lights.

When parked on a one-way street, lights may still be required to provide visibility to oncoming traffic or vehicles following the same direction. Being parked 10m from a lighted street lamp isn't a blanket rule that negates the need for lights; instead, it is often safer to leave them on to increase visibility. In a designated parking area, like a parking lot or garage, it is safer and more customary to leave the lights on to alert other vehicles and pedestrians of your presence, especially if the area may have poor lighting conditions. Thus, the condition of daylight provides the clearest indication that lights don’t need to be kept on.