Criminal Law

Defenses to Speeding Violations

Generally, ignorance or mistake of fact is not a defense to a charge of speeding. So, claims that a driver didn't know the speed limit, or didn't know that he or she was speeding because of a defective speedometer, will not stop a conviction for speeding.

In some states, "legal justification" defenses are available in speeding prosecutions. For example, where a driver is speeding because someone is holding a gun to the driver's head, the speeding is not a voluntary act, and so the driver can't be convicted of speeding.

However, in some states, courts have rejected the "legal justification" defense in speeding cases. So, in such a state, for example, the fact that a driver exceeds the speed limit in order to pass the traffic in the right lane and make way for a police cruiser that was on an emergency run won't bar a conviction for speeding.

When confronted with a charge of speeding, it is important that you understand the speeding laws in your area and the possible defenses that can be raised.

Legal Justification

"Legal justification" defenses generally available when the driver is charged with speeding include: (1) when a driver's speeding was caused by the actions of the police or other law enforcement officers, (2) self-defense and the defense of others, (3) coercion, (4) necessity and (5) entrapment.

For example, a motorist's claim that he exceeded the speed limit to get away from a police car that was being driven in a wild and erratic manner, causing him to fear a physical confrontation with the officer-driver, can be sufficient to avoid a conviction for speeding.

Speeding in response to an emergency that was caused by the actions of someone or something other than the police can be a valid defense to a speeding charge.

A motorist can raise this "sudden emergency doctrine" only when the alleged emergency made it impossible to comply with the speeding statute or ordinance. But, if the emergency could have been avoided by the driver slowing his or her vehicle, there is no excuse or justification for the speeding.


  • When a driver accelerates quickly and exceeds the speed limit as the only way to avoid a rear-end collision with a car that suddenly slows down in front of him, the excessive speed might be justifiable.
  • However, in the same situation, the speeding will not be justified if it can be shown that the driver could have avoided the collision by slowing his car.

Identity of the Driver

There can be no conviction for speeding when the prosecution doesn't prove that the defendant was in fact the driver of the speeding vehicle. The identity of the defendant as the driver was established in instances such as:

  • The defendant was shown to have been in physical control of a speeding vehicle shortly before the police arrived at the scene, and
  • The defendant made a statement to the arresting officer that he had driven his truck into the ditch where it was found, and the defendant's girlfriend was found sitting in the passenger seat

On the other hand, the driver's identity was not established in instances such as:

  • Where the only connection between the defendant and the vehicle was the fact that the defendant was discovered driving the vehicle 90 minutes after it was involved in an accident
  • The defendant denied driving the vehicle at the time of the alleged offense and there was no evidence to establish that the defendant was driving at that time

Identity can be proved through direct evidence, such as an eyewitness who saw the defendant driving, or through circumstantial evidence, such as where soon after a witness saw skid marks on the highway and dust in the air, the police found the defendant alone in a vehicle that was lying on its top with its doors and windows closed.

Some state laws contain presumptions with respect to drivers and vehicles. For instance, under some state laws, it is presumed (meaning accepted or assumed) that the owner of a vehicle was its operator at the time of a speeding violation. In other states, ownership of a vehicle does not justify a presumption that the owner was the driver at the time of the violation.

Again, it is critical that you understand the speeding laws in your state and whether any presumptions apply when you are planning a defense to a charge of speeding.

Identity of the Vehicle and "Selective Enforcement"

Another defense that might be used in a speeding case is the identity of the speeding vehicle.

This issue of identity comes into play most often when the case is based on radar device evidence, and more than one vehicle might have been in the zone where the radar gun or laser device was pointed. In such a case, the prosecution must introduce evidence to prove that the defendant's vehicle was the vehicle found to have been speeding.

In addition, while an officer's reason for stopping a particular motorist normally is not considered in speeding cases, it will be looked at under certain circumstances. Selective enforcement on the basis of race or other discriminatory factors can provide a defense if the driver can show, for instance, that he or she was stopped by the police because he or she was African-American.

Jurisdiction of Law Enforcement

The lack of jurisdiction or authority of a particular police force or department to enforce the speed laws in the place where the defendant was stopped is an affirmative defense. In most states, the defendant has the burden of proof to establish an affirmative defense. So, in such a state, the driver will have to produce evidence that the police officer didn't have the legal authority to stop the driver for speeding.

In many states, there is an exception for "hot pursuit," that is, when a defendant speeds in one jurisdiction, a suburb or town, for example, and a police officer from that suburb follows the car outside of the officer's jurisdiction into the next suburb to stop or apprehend the driver.

Related Resources on Lawyers.comsm

- Speeding Laws
- Enforcing a Speeding Violation
- Traffic Violations articles and information
- Selecting a Good Criminal Lawyer
- Find a Criminal Lawyer in your area
- Visit Our Traffic Citations Message Board or Criminal Law Message Board for more help

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