29-A M.R.S. §1905: Rear lights

1. Requirement. Except as provided in subsection 3, a motor vehicle with 3 or more wheels or a tiny home, trailer or semitrailer must have on the rear 2 lights, one on each side of the axis, each capable of displaying a red light visible for a distance of at least 100 feet behind the vehicle.

2. Vehicles used in conjunction. When a vehicle is used in conjunction with another vehicle, only the last must carry the lights.

3. Vehicles manufactured with one rear light. If a vehicle was manufactured with only a single rear light, that light is sufficient if the light complies with the visibility requirement and is in the center or to the left of the vehicle's axis.

4. Exception for farm tractors. This section does not apply to unregistered farm tractors.