Are emergency lights legal to be mounted in the rear window sill?

The correct answer is that emergency lights can legally be mounted in the rear window sill, provided they do not obstruct the driver's rear view. This regulation is in place to ensure that while emergency lights are visible to other drivers, they do not interfere with the operator's ability to see out of the vehicle. Clear visibility is crucial for safe driving, and any modifications to the vehicle, such as the installation of emergency lights, must comply with laws intended to promote safety.

The stipulation that the lights should not obstruct the rear view reinforces the balance between having emergency signaling equipment and maintaining safe driving conditions. Thus, as long as the emergency lights are positioned appropriately and allow for unobstructed visibility, their use in the rear window sill is permissible.