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18 U.S.C. 39 - Traffic Signal Preemption Transmitters

Let's review the federal offense of unauthorized sale or use of traffic signal preemption transmitters defined under Title 18 U.S. Code 39.

Like many states that have laws criminalizing the unauthorized use of traffic signal preemption transmitter devices, selling or using these devices unlawfully becomes a federal crime when interstate or foreign commerce is affected.

This law is embodied in Title 18 U.S. Code 39. Simply put, this statute makes it a federal offense to sell traffic signal preemption transmitters or to use them.

Traffic Signal Preemption Transmitters – 18 U.S.C. 39
It's a federal crime to use or sell traffic signal preemption transmitters affecting interstate commerce.

18 U.S.C. 39(a) offense says, "(1) Sale, whoever, in or affecting interstate or foreign commerce, knowingly sells a traffic signal preemption transmitter to a nonqualifying user shall be fined under this title, or imprisoned not more than one year, or both.

(2) Use, whoever, in or affecting interstate or foreign commerce, being a nonqualifying user, makes unauthorized use of a traffic signal preemption transmitter shall be fined under this title or imprisoned not more than six months, or both.”

A “traffic signal preemption transmitter” means any mechanism changing or altering a traffic signal's phase time or sequence.

A “nonqualifying user” means someone who uses a traffic signal preemption transmitter and is not acting on behalf of a public agency or private corporation authorized by law.

If you're convicted at the federal level of selling or using one of these transmitters unauthorized, you can face up to 1 year in prison and up to $100,000 in fines.

What is the Historical Context and Purpose?

18 U.S.C. 39 was instituted in response to the advent of advanced traffic control technology. Traffic signal preemption transmitters are devices used primarily by emergency vehicles, law enforcement, and other public service vehicles to control traffic signals, ensuring a clear path during emergencies or high traffic times.

Misusing these devices poses significant risks to traffic flow and public safety. The law was enacted to deter unauthorized individuals from manipulating traffic patterns for personal gain or malicious intent.

What Does the Law Say?

Simply stated, Title 18 U.S.C. 39 makes it a federal crime to knowingly do either of the following while "affecting interstate or foreign commerce":

  • To sell a traffic signal preemption transmitter to a nonqualifying user or
  • To use a traffic signal preemption transmitter as a nonqualifying user.

Other things to know about this law:

  • For purposes of this law, "affecting interstate or foreign commerce" refers to any action involving crossing state or international boundaries. Examples include vehicles conducting business across state or international lines, using the device to impact interstate trucking routes, or using the device in a commercial vehicle running business across state lines.
  • A "traffic signal preemption transmitter" refers to any device or equipment that controls or manipulates a traffic signal's sequence or phase timing. This includes both hardware and software systems.
  • A "nonqualifying user" refers to anyone using the transmitter who "is not acting on behalf of a public agency or private corporation authorized by law to provide fire protection, law enforcement, emergency medical services, transit services, maintenance, or other services for a Federal, State, or local government entity." The law makes an exception for users who are using the devices for "classroom or instructional purposes."

What Are Some Examples?

EXAMPLE 1: Ted is an interstate truck driver with an aggressive delivery route through high-traffic areas. To help improve his delivery times, he acquires a traffic signal preemption device and uses it sparingly to help him avoid stopping at traffic signals during rush hour. Ted can be charged with a federal crime under 18 U.S.C. 39 because he is involved in interstate commerce and is not a qualified user.

EXAMPLE 2: John was recently fired from a national distribution center job. In retaliation, he buys a traffic signal preemption device from Ginny, who works for a manufacturer of the devices. John parks along a major traffic route leading to the facility and uses the device to disrupt the flow of trucks in and out of the distribution center.

In this scenario, both John and Ginny could be charged under 18 U.S.C. 39—John for using the device to disrupt interstate commerce and Ginny for selling it to him.

EXAMPLE 3: Jerry is an instructor at a local police academy. He instructs trainees on a field trip to a traffic signal intersection during a low-traffic time on using a traffic signal preemption transmitter. Since Jerry is using the device for official instructional purposes, he is not guilty of a crime under 18 U.S.C. 39.

What are the Related Federal Laws?

18 U.S. Code Chapter 2 Aircraft and Motor Vehicles has several federal laws that are related to 18 U.S.C. 39 traffic signal preemption transmitters, including the following:

  • 18 U.S.C. 31 - Definitions;
  • 18 U.S.C. 32 - Destruction of aircraft or aircraft facilities;
  • 18 U.S.C. 33 - Destruction of motor vehicles or motor vehicle facilities;
  • 18 U.S.C. 34 - Penalty when death results;
  • 18 U.S.C. 35 - Imparting or conveying false information;
  • 18 U.S.C. 36 - Drive-by shooting;
  • 18 U.S.C. 37 - Violence at international airports;
  • 18 U.S.C. 38 - Fraud involving aircraft or space vehicle parts;
  • 18 U.S.C. 39A - Aiming a laser pointer at an aircraft;
  • 18 U.S.C. 39B - Unsafe operation of unmanned aircraft;
  • 18 U.S.C. 40 - Commercial motor vehicles required inspection stop;
  • 18 U.S.C. 40A - Operation of unauthorized aircraft over wildfires;

What Are the Penalties for 18 U.S.C. 39?

If you are convicted of either unauthorized use of a traffic signal preemption transmitter or selling a transmitter to a nonqualifying user, you could face either or both of the following penalties under federal law:

  • Up to 1 year in federal prison; and
  • Up to $100,000 in fines.

What Are the Defenses for 18 U.S.C. 39?

If you're charged with violating 18 U.S.C. 39, a skilled federal criminal defense attorney can utilize one or more defense strategies to combat the charges, as discussed below.

Defenses for Traffic Signal Preemption Transmitters
Contact our federal defense lawyers for advice.

Perhaps we can argue that there was a lack of knowledge. Prosecutors must prove you knowingly used or sold the device unlawfully to convict you. Your attorney may say, for example, that you were unaware that you were not qualified to use the device or that you sold it to someone you did not know was a nonqualifying user.

Perhaps we can argue that you were a qualifying user. Your attorney may argue that you were a qualifying user, such as an authorized public official, who was using the device within the scope of their duties.

Perhaps we can argue that there was an absence of use: You can't be convicted under this law simply for possessing the device as a nonqualified user; prosecutors must show you used the device in a nonqualifying manner.

If your attorney can demonstrate you had the device but did not use it, you may be able to get the charges dismissed. Contact us to review the case details and legal options. Eisner Gorin LLP has offices in Los Angeles, California.

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