Mont. Code Ann. § 61-9-402

(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.

(10) A violation of subsection (5) is considered reckless endangerment of a highway worker, as provided in 61-8-301(4), 61-8-389(2), and is punishable as provided in 61-8-715.

(2) An authorized emergency vehicle must be equipped:

(a) with a siren and an alternately flashing or rotating red light as specified in this section; and

(b) with signal lamps mounted as high and as widely spaced laterally as practicable that are capable of displaying to the front two alternately flashing red lights located at the same level and to the rear two alternately flashing red lights located at the same level. These lights must have sufficient intensity to be visible at 500 feet in normal sunlight.

(3) A bus used for the transportation of school children must be equipped with signal lamps mounted as high and as widely spaced laterally as practicable, displaying to the front two red and two amber alternating flashing lights and to the rear two red and two amber alternating flashing lights. These lights must have sufficient intensity to be visible at 500 feet in normal sunlight. The warning lights must be as prescribed by the board of public education and approved by the department.

(3) (a) A bus used for the transportation of school children must be equipped with signal lamps mounted as high and as widely spaced laterally as practicable, displaying to the front at least two red and two amber alternating flashing lights and to the rear at least two red and two amber alternating flashing lights. These lights must have sufficient intensity to be visible at 500 feet in normal sunlight.

(b) Additional red flashing lights may be mounted to the front and to the rear at a height of at least 36 inches and not more than 72 inches from the ground. If additional red lights are mounted, they must be installed so that they can be actuated only if the school bus is stopped.

(c) The specifications for the warning lights must be prescribed by the board of public education and approved by the department.

(4) A police vehicle and an authorized emergency vehicle may, and an emergency service vehicle must, be equipped with alternately flashing or rotating amber lights as specified in this section.

(5) The use of signal equipment as described in this section imposes upon the operators of other vehicles the obligation to yield right-of-way or to stop and to proceed past the signal or light as provided in 61-8-346 61-8-387 and 61-8-388 subject and subject to the provisions of 61-8-209 and 61-8-303.

(6) An employee, agent, or representative of the state or a political subdivision of the state or of a governmental fire agency organized under Title 7, chapter 33, who is operating a police vehicle, an authorized emergency vehicle, or an emergency service vehicle and using signal equipment in rendering assistance at a highway crash scene or in response to any other hazard on the roadway that presents an immediate hazard or an emergency or life-threatening situation is not liable, except for willful misconduct, bad faith, or gross negligence, for injuries, costs, damages, expenses, or other liabilities resulting from a motorist operating a vehicle in violation of subsection (5).

(7) Blue, red, and amber lights required in this section must be mounted as high as and as widely spaced laterally as practicable and be capable of displaying to the front two alternately flashing lights of the specified color located at the same level and to the rear two alternately flashing lights of the specified color located at the same level or one rotating light of the specified color, mounted as high as is practicable and visible from both the front and the rear. These lights must have sufficient intensity to be visible at 500 feet in normal sunlight. Except as provided in 61-9-204(6), only police vehicles, as defined in 61-8-102, may display blue lights, lenses, or globes.

(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.

(9) Only a police vehicle or an authorized emergency vehicle may be equipped with the means to flash or alternate its headlamps or its backup lights.

Audible and visual signals on police, emergency vehicles, and on-scene command vehicles -- – immunity