Some state driving laws are so specific that they sound like something someone made up for a trivia contest. Yet buried in actual regulations are rules covering everyday items that might be sitting in a truck cab or attached to the vehicle itself.

The wording can be surprisingly entertaining, especially when lawmakers make distinctions that seem oddly precise. And unlike the questionable lists of bizarre laws that circulate online, these examples can be traced to published state regulations.

Maine Gives Road Maps a Pass

A paperback and a road atlas might sit side by side in a truck, but Maine’s law treats them differently once the vehicle is moving. Reading books, newspapers, brochures, and similar printed material while driving is prohibited. Maps and written directions to a particular destination, however, are specifically exempt.

The distinction dates back to 1999, when paper maps were still an essential part of traveling unfamiliar roads. Although navigation has changed considerably since then, the wording remains a reminder of the days when unfolding a road atlas was part of planning a trip.

It also leaves Maine with a rather specific rule: reading directions is permitted under the exemption, but catching up on a favorite novel isn’t.

Colorado’s Headphone Rule Comes Down to One Ear

A headset might be one of the most familiar accessories in a truck cab, particularly for anyone who spends time talking with dispatch or family while traveling. Colorado’s law makes an important distinction between different types of listening devices.

The state generally prohibits wearing earphones while operating a motor vehicle, but allows certain devices covering only one ear when they’re connected to a wireless telephone. A qualifying single-ear phone headset is therefore treated differently from a pair of headphones covering both ears.

For professional drivers, the distinction is particularly recognizable. Single-ear communication headsets have long been part of the industry, and Colorado’s exception specifically accounts for that type of device. Federal commercial driving requirements still apply, regardless of the state provision.

Maine Has a Preferred Spot for Light-Up Truck Signs

Decorative lighting has been part of truck customization for decades, although Maine’s rules about illuminated signs are unusually detailed. Rather than simply allowing or prohibiting every lighted display, the state distinguishes between certain business identification signs and general advertising.

Qualifying illuminated identification signs are permitted on commercial vehicles, but their placement is restricted. On a truck tractor, the designated location is the roof-mounted wind deflector. Semitrailers have separate placement requirements, and the signs cannot use flashing, blinking, or neon lighting.

It’s an oddly precise set of specifications for something that might otherwise seem like a simple accessory. The law addresses not only what a sign can display, but exactly where it belongs on the equipment.

Michigan Separates Television From Navigation

A screen in a modern truck can serve several purposes, from showing a route to displaying camera footage. Michigan’s law makes a distinction between those functions and entertainment video that a driver could watch while the vehicle is moving.

The state restricts television and similar video displays visible to the operator during travel, while allowing certain navigation systems, vehicle information displays, and camera equipment. The rules also address the placement of some aftermarket devices, including restrictions intended to preserve visibility and avoid interference with vehicle controls.

That means the legal difference isn’t necessarily the size or appearance of the screen. A display showing the next turn serves a different purpose from one playing a television program, even if both use similar technology.

Washington Gets Specific About Tire Studs

Washington’s winter tire regulations contain a detail that could easily be mistaken for an internet trivia question. A qualifying studded tire must have at least 70 metal studs when sold or installed, and at least 56 must remain for the tire to continue meeting the standard.

The specifications don’t stop at the numbers. The studs must be metal with tungsten carbide tips, and seasonal restrictions determine when approved studded tires can be used on public roads.

There’s an important distinction for commercial trucking. Washington generally prohibits metal-studded tires on vehicles weighing 10,000 pounds or more, with limited exceptions. The numerical requirements therefore apply to qualifying studded tires rather than giving heavy trucks permission to use them.

While the rule serves a practical purpose, the fact that state regulations specify a minimum number of individual tire studs makes it one of the more unexpected details in this collection.

There’s Always Another Strange Law Out There

The laws that make the best road trivia aren’t necessarily the oldest or the most outrageous. Sometimes they’re simply the ones that leave people wondering how a particular detail ended up in the rulebook.

With 50 states maintaining their own motor vehicle laws, there’s plenty more unusual wording waiting to be found. Some provisions have been around for decades, while others have changed alongside the equipment people use. That makes checking the original law part of the fun, especially when the real explanation turns out to be something nobody expected.

Frequently Asked Questions

Why do states have different rules for vehicle accessories?

States have authority to regulate vehicle equipment and driving practices within their jurisdictions, subject to applicable federal requirements. Their laws have developed at different times and may address local conditions or equipment that was common when the provisions were adopted.

Do unusual state driving laws ever get repealed?

Yes. State legislatures can amend or repeal existing laws, and transportation regulations may change as vehicle technology develops. An unusual law mentioned in an older article may no longer be in effect.

Where can the original wording of a state driving law be found?

State legislature websites typically publish their statutes, while state agencies may maintain separate administrative regulations. These official records are useful for checking whether a law is current and whether exceptions apply.

Are all vehicle equipment rules found in state driving laws?

No. Commercial vehicles may also be subject to federal requirements, and some equipment standards appear in administrative regulations rather than the main state vehicle code.

The TDUSA editorial team creates practical, driver-focused content covering trucking news, industry updates, safety, regulations, and career information for professional truck drivers across the United States. Each article is built to reflect real-world experience, industry developments, and information drivers can use on and off the road.

Last Updated: November 11, 2026