How to Research Traffic Laws

Find the Law That Supports Your Position

1.     Determine What You Are Charged With

The first thing you need to do is find the exact words of the law you are charged with breaking. In some states, traffic laws are set out in a “Vehicle Code,” while in others they are gathered as part of a “Transportation Code,” “Motor Vehicle Laws,” or under some similar name. No two states have exactly the same traffic laws, but most are very similar.

Look for a number on your ticket that corresponds to the law (often called a “statute” or “vehicle code section”) you are charged with violating. Sometimes it will be hand printed by the officer in a box or blank; other times it’s preprinted on the ticket, with the officer simply checking the appropriate box. In either case, near the statute number you will often find a very short description of the law (for example, “VC [Vehicle Code Section] 22350—exceeding posted speed”). For speeding violations, in most states you’ll also find the speed the officer claims you were going, as well as the posted speed limit on the road where you were stopped. Next you must look up and read the law the officer claims you violated.

2.     Find Your Law Online

The fastest way to find your state’s traffic laws is to search online. On your state’s website, you can either do a search for the code number of the law or you can scroll through the index of laws usually highlighted on the state’s home page. Another option is to google the name of your state and the name of the code or the title of the law.  For example, googling “Vermont excessive speed” results in several entries for Vermont Code § 1097, which sets out the law regarding excessive speed.Be sure you are reading current law.

3.     Review the Law

Once you find the law you are charged with, read it carefully to determine which facts the prosecution will have to prove to convict you. Many laws are complex. In fact, they are often so convoluted that it’s not uncommon to find, upon careful reading, that what you did was not, technically speaking, a violation of the exact words of the statute. Always ask yourself the question: What are the elements (or parts) of the offense I am charged with committing?

For example, in most states the law ­making U-turns illegal reads like this:

No person in a residence district shall make a U‑turn when any other vehicle is approaching from either direction within 200 feet, except at an intersection when the approaching vehicle is controlled by an official traffic-control device.

You should break this law down into its elements by drawing a line between each clause, like this:

No person in a residence district / shall make a U-turn / when any other vehicle is approaching from either direction / ­within 200 feet / except at an ­intersection / when the approaching vehicle / is ­controlled / by an official traffic-control device.

Focusing on each element of a law is often the key to unlocking an effective ­defense. That’s because to be found guilty of having made this illegal U-turn, the state must prove you violated every element of the offense. In this case, the state would have to show specifically that:

  1. You were driving in a “residence ­district”
  2. You drove your vehicle in a 180-­degree turn, or “U-turn”
  3. Another vehicle was approaching within 200 feet or fewer, in front of or behind you, and
  4. An “official traffic-control device” at an “intersection” was not controlling the vehicle approaching you.

If you can show that your conduct didn’t violate any element of a traffic law, then the law was not violated and the charge should be dismissed. For example, you should be found not guilty if the area where you were ticketed was not a “residence district,” or the vehicle the officer claims was approaching was more than 200 feet away, or you were at an intersection controlled by an “official traffic control device.”

This type of word-by-word reading of statutes may seem hyper-technical, but it is commonly employed by lawyers and judges. The American legal system is built on the concept that you are innocent unless the state can prove you committed some clearly defined conduct—for example, driving a motor ­vehicle faster than 65 mph on a public road. (Note that even if you conclude you really have violated every element of a law, your case is not hopeless.

4.      Find Support For Your Position

You’re probably going to need legal support for your position. But before you spend time researching the law keep one rule in mind: If the law you are charged with violated is simple and clear,  legal research probably won’t help. However, if the law is not clear and lends itself to various interpretations, legal research may pay off. Here’s how it works:

Once a law is written, judges use real-life situations to interpret it. Sometimes these decisions (called cases) will make a huge difference to your situation. For example, in all states, speeding for the purpose of being a show-off is a crime called “exhibition of speed.” But an appeals court in California expanded the law to include screeching a car’s tires (or burning rubber) to impress listeners who can’t necessarily see you. This unusual expansion of the words “exhibition of speed” is something you would never know by reading the law alone.

5.     Find Cases: For a Fee and For Free

One way to learn more about how a law has been interpreted is to look for your state’s annotated codes. Annotated codes are a set of laws that contain summaries of court decisions beneath each entry. Private Internet services such as LexisNexis, Versuslaw, and FindLaw provide annotated codes—as well as case decisions—but you’ll have to pay a fee to access them. (We recommend Versuslaw, as it is the least expensive service, and you can use your credit card to pay for services.)

You may also be able to find case law regarding certain types of motor vehicle statues for free by using an Internet search engine such as Google Scholar (Check the box “Legal Opinions and Journals” and type in the vehicle code.

6.     Analyze Court Decisions

Whenever possible, look at the actual case dealing with the vehicle code (not just the summary in the annotated codes. For some helpful free information online, check out Nolo’s information on legal research website (, which contains detailed information on how to do legal research, including how to find and interpret cases.

How Citations Work

Decisions of a state’s highest court look like this: 155 Cal 422. The first number refers to the 155th volume of California Supreme Court decisions (Cal = ­California), and the second number directs you to page 422. Similarly, 55 Pa. 345 refers to the 55th volume of the decisions of the Pennsylvania Supreme Court, page 345. In addition, many case cita­tions also may list a 2d, 3d, or 4th after the state abbreviation. Each refers to one of the chrono­logical series of case volumes for that state. For example, the 2nd series might cover cases from 1960 to 1985, and the 3rd series 1986 to the present.

Other Sources for Research

Since each law is written to deal with a very specific action (for ­example, exceeding the speed limit), other laws may also have a bearing on your case. Or put another way, the legal interpretation of one traffic law can sometimes affect another.

For example, Section 123.45.678 of your state’s motor vehicle law forbids exceeding 25 mph in a residential district. But section 123.45.605 says all your state’s speed limits are “presumed” limits. This means even though you may have technically violated Section 123.45.678, you might be able to successfully claim that it was legal to do so because Section 123.45.605 allows you to exceed the speed limit when driving safely under the

To find information about other laws related to your case, like these here, you will have to search the annotated codes using terms that you believe relate to your ticket. (If you’re doing your research using the hard copy books in the library, look up relevant subjects in the index.) Then you need to look up the laws related to those subjects and look for the “annotated” cases listed below the code, just as you did above. l

In addition to this website are some other websites you can use to help you research your case:


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