Montana vehicle lighting laws

Below are all relevant excerpts from Montana Vehicle Code that limit, restrict or allow certain aftermarket lights to be installed on vehicles.

61-9-209. Color of clearance lamps, side marker lamps, reflectors, and backup lamps.

(1) Front clearance lamps and those marker lamps and reflectors mounted on the front or on the side near the front of a vehicle must display or reflect an amber color.

(2) Rear clearance lamps and those marker lamps and reflectors mounted on the rear or on the sides near the rear of a vehicle must display or reflect a red color.

(3) All lighting devices, reflectors, and stoplights mounted on the rear of a vehicle must display or reflect a red color, except:

• (a) the signal devices, as defined in 61-9-218;
• (b) the light illuminating the license plate that must be a white lamp; and
• (c) the light emitted by a backup lamp that must be white.

61-9-219. Additional lighting equipment.

(1) Any motor vehicle may be equipped with not more than two side cowl or fender lamps which shall emit an amber or white light without glare.

(2) Any motor vehicle may be equipped with not more than one running board courtesy lamp on each side thereof which shall emit a white or amber light without glare.

(3) Any motor vehicle may be equipped with not more than two backup lamps either separately or in combination with other lamps, but any such backup lamps shall not be lighted when the motor vehicle is in forward motion.

(4) Any vehicle may be equipped with lamps which may be used for the purpose of warning the operators of other vehicles of the presence of a vehicular traffic hazard […] shall display simultaneously flashing white or amber lights, or any shade of color between white and amber. […]

61-9-226. Special restrictions on lamps — definition.

[…] (2) A person may not drive or move a vehicle or equipment upon a highway with a lamp or device displaying a red light visible from in front of the center of the vehicle. This section does not apply to a vehicle upon which a red light visible from the front is expressly authorized or required by this code

(3) Flashing, blinking, sequential, rotating, or pulsating lights are prohibited except on vehicles that are authorized by this chapter to contain the lights or on a vehicle as a means for indicating a right or left turn or the presence of a vehicular traffic hazard requiring unusual care in approaching, overtaking, or passing.

(4) License plate decorative lighting that is not original manufacturer’s equipment or undercarriage decorative lighting that rotates, flashes, or oscillates or that displays a color authorized by this chapter for use by police vehicles and authorized emergency vehicles may not be illuminated on a vehicle that is operated upon a highway or street.

61-9-402. Audible and visual signals on police, emergency vehicles, and on-scene command vehicles — immunity.

(1) A police vehicle must be equipped with a siren capable of giving an audible signal and may be equipped with alternately flashing or rotating red or blue lights as specified in this section. […]

(8) A police vehicle and authorized emergency vehicle may be equipped with a flashing signal lamp that is green in color, visible from 360 degrees, and attached to the exterior roof of the vehicle for purposes of designation as the on-scene command and control vehicle in an emergency or disaster. The green light must have sufficient intensity to be visible at 500 feet in normal sunlight. Only the on-scene command and control vehicle may display green lights, lenses, or globes.