Traffic Laws: Purposes & Principles (June 2025)

Who Makes and Enforces Traffic Laws?

To avoid confusion and inconsistencies on roads and highways, the Federal Highway Administration publishes the Manual on Uniform Traffic Control Devices (MUTCD). This document sets nationwide specifications for traffic lights, road signs and other types of traffic signals.

While there are federal standards, state legislatures are responsible for creating state-level safety laws. State highway patrols and local law enforcement agencies handle enforcement.

The Purpose and Principles of Traffic Laws

Traffic laws serve a broad range of purposes, including:

• Protecting the safety of drivers, pedestrians and cyclists
• Promoting general order
• Maximizing traffic efficiency
• Assigning accountability for accidents and violations

While no one enjoys getting a traffic ticket, the existence of traffic rules is essential to safe, functioning roadways.

Common Driving Rules Shared Across the U.S.

If each state had drastically different traffic laws, car accidents would be a more common occurrence. Fortunately, many of the most fundamental laws are fairly standardized.

Yielding to Pedestrians and Cyclists

Pedestrians and cyclists are uniquely vulnerable road users. What might seem like a very minor accident to a driver could prove to be fatal for someone walking or riding a bike. As a result, each state requires drivers to yield to cyclists and pedestrians, even if they’re not in a crosswalk or designated bike lane.

Using Turn Signals

Turn signals play an important role in preventing auto accidents. All states require the use of turn signals, and they often place special emphasis on the importance of signaling and checking blind spots before switching lanes.

Banning Dangerous Behaviors

While penalties differ depending on the jurisdiction, each state bans potentially dangerous driving behaviors like these:

• Driving under the influence (DUI) of drugs or alcohol
• Driving too far over the speed limit
• Street racing

Although these behaviors are illegal, the specifics of enforcement differ by state. For example, the legal alcohol limit in most states is 0.08%, but in Utah, it’s 0.05%.

Keeping Cars in Working Order

Not all states require cars to pass inspections. However, to reduce the risk of car and truck accidents, all states tend to require drivers to ensure headlights and taillights, windshield wipers and other critical pieces of equipment are functional.

State-Level Variations in Traffic Laws

States share many traffic laws, but there’s still significant variation from state to state. These are some notable areas where state laws differ:

Seat Belt Laws

Many people mistakenly believe that all 50 states and Washington, D.C. require seat belt use. Most states do, but New Hampshire is the exception — it doesn’t require adults in front seats to wear seat belts, although it’s still a good idea to do so.

Insurance Requirements

Most states require that drivers carry insurance or prove that they can be financially responsible if they cause an accident. However, each state is free to set its own minimum coverage amounts.

Use of Driver’s License Point Systems

All states require drivers to be licensed. Many of them use a point system to track driving records and determine when someone’s license should be suspended. With this system, each traffic offense has a set point value. Once a driver has accumulated a set number of points, their license can be suspended.

Many states have some variation of this system. However, others penalize repeat offenders in different ways.

Traffic Sign Rules and Interpretations

Traffic signs didn’t get their shapes and colors by mere accident. They’re part of a standardized system to help drivers understand their surroundings and stay safe while driving. Traffic signs fall into three main categories:

Regulatory Signs

These signs are usually red, white or blue, and they communicate traffic laws. The most common examples are stop signs, speed limit signs and yield signs.

Warning Signs

These signs communicate potential hazards like falling rocks or sudden curves. They’re usually school-bus yellow with black symbols.

Guide Signs

These signs are generally green, blue or brown, and they’re commonly found on interstates. They guide drivers along routes and to destinations.

The Role of Technology in Traffic Law Enforcement

Most states use traffic cameras in some capacity, even if it’s just to monitor the roads. However, some states allow drivers to receive fines and tickets from cameras that catch them speeding or running red lights.

Some states that allow the use of traffic camera tickets require signs warning drivers that they’re in an area with camera enforcement. In other states, the cameras may be completely hidden.

Penalties for Violating Traffic Laws

Penalties for traffic law violations vary depending on the nature of the offense, where it occurred, and the driver’s existing record. They often include one or more of the following:

• Fines
• Addition of points to your license
• Required attendance at traffic school
• Increased insurance premiums
• License suspension

Some severe traffic violations, like DUI, are criminal offenses. These violations may result in arrest and even imprisonment.

Have You Been Accused of a Traffic Offense?

If you’ve received a traffic citation because of confusion over state traffic laws, an experienced traffic ticket lawyer may be able to help. Not sure how to start your search for the right attorney? ConsumerShield can help.

Our knowledgeable team is dedicated to empowering consumers like you. We don’t just provide educational resources — we also match consumers in need of legal advice with qualified attorneys in their area. Fill out our form to start with a free case evaluation today.