Delaware Caps Fog, Driving and Spot Lamps by Height and Count

Subchapter II of chapter 43 of Title 21 is written as a permission list rather than a prohibition list, which is why aftermarket lighting in Delaware is so tightly bounded. Section 4346 states each allowance with a count and, for everything but spot lamps, a mounting height measured above the level surface on which the vehicle stands. Spot lamps under § 4346(a) are capped at two and must be aimed so that no part of the high intensity portion of the beam goes to the left of the extreme left side of the vehicle, or more than 100 feet ahead, when approaching another vehicle. Fog lamps under § 4346(b) are capped at two, must sit between 12 and 30 inches, and must be aimed so that at 25 feet ahead none of the high intensity portion left of the vehicle centre rises higher than 4 inches below the centre of the lamp. They may be used with the low beam. The auxiliary passing lamp under § 4346(c) is limited to one, between 24 and 42 inches. The auxiliary driving lamp under § 4346(d) is limited to one, between 16 and 42 inches. Both auxiliary lamps are pulled into the beam-selection rules of § 4349, which requires an upper beam revealing persons and vehicles at 350 feet and a lower beam revealing them at 100 feet without striking the eyes of an approaching driver.

Two further sections do most of the enforcement work. Section 4352(b) says that where a vehicle already has the required head lamps and also carries auxiliary lamps, a spot lamp, or any other front lamp projecting a beam greater than 300 candlepower, no more than four of those lamps may be lighted at any one time on a highway. That is the rule a light bar most often breaks, because the bar counts against the same total as the headlights and fog lamps. Section 4353(a) then takes any lighted lamp or illuminating device other than head lamps, spot lamps, auxiliary lamps, flashing turn signals, emergency vehicle warning lamps and school bus warning lamps that projects more than 300 candlepower, and requires it to be aimed so that no part of the high intensity portion of the beam strikes the roadway more than 75 feet from the vehicle. Rock lights, chase lights, bed lights and similar accessories fall into that residual category.

Colour and flashing are handled separately and strictly. Section 4353(b) forbids driving or moving any vehicle on a highway with a lamp or device displaying a red light visible from directly in front of its centre, unless a red forward light is expressly authorised elsewhere in the subchapter. Section 4353(c) prohibits flashing lights except on an authorized emergency vehicle, a school bus, snow removal equipment, a vehicle authorised by the Secretary of Safety and Homeland Security in the interest of public safety, or as a turn or hazard signal, plus one narrow modern carve-out: a motorcycle, moped or motorized scooter brake light system in which the lamp pulses rapidly for no more than 5 seconds after the brake is applied and then holds steady. Delaware also permits motorcycle underglow, but only in two colours: § 4346A(b) allows LED ground effect lighting attached to the underbody that emits a nonflashing amber or white light. Green revolving or flashing lights are reserved by § 4356A to fire and police vehicles, vehicles the Secretary designates as emergency vehicles, and state or municipal snow removal equipment, and even then only at a command post, en route as a hazardous material response vehicle, or during cold weather operations. Blue and white flashing lights belong to fire chiefs, deputy and assistant chiefs, chief engineers, fire police officers and chief EMS officers under § 4356(a).

One allowance is on a timer. Section 4348 is printed twice in the Delaware Code, once as "[Effective until June 30, 2030]" and once as "[Effective June 30, 2030]", with the in-force version printed first. The current text at § 4348(d)(3)b. permits modulating headlights on motorcycles that conform to 49 C.F.R. § 571.108 S10.17.5, notwithstanding § 4353(c). In the version taking effect on 30 June 2030 that paragraph reads simply "[Repealed.]", so motorcycle headlight modulators are a lawful accessory in Delaware today and are scheduled to stop being one. Section 4355(b) is the catch-all that keeps the whole scheme closed: additional parts and accessories are allowed only where "not inconsistent with this subchapter."

21 Del. 75 nor more than $100. Section 4358 also lists the lighting offences that may be dismissed before trial on proof that repairs have been made so the vehicle complies, and the list is short: §§ 4333, 4334, 4336, 4337 and 4351, covering head lamps, tail lamps, stop lamps and turn signals on new vehicles, and motor-driven cycle lighting. An illegal auxiliary lamp under § 4346, an over-count under § 4352(b), or a flashing or red forward light under § 4353 is not on that list, so removing the offending lamp does not carry the statutory route to dismissal.

Section 4355(a) adds a separate and heavier exposure: it is a misdemeanour to drive, or for an owner to knowingly permit to be driven, a vehicle that is equipped in any manner in violation of the subchapter. Under 11 Del. § 4206(c) an unclassified misdemeanour with no stated sentence carries up to 30 days at Level V and a fine up to $575. Enforcement also runs through 21 Del. § 2144(a), under which any police officer may on reasonable cause require the vehicle to stop and submit to further inspection and issue a written notice requiring a certificate of inspection and approval within 5 days.