September 29, 2008 By Wallin & Klarich

The California Highway Patrol utilizes fixed wing aircraft to nail speeders on highways. The California Department of Transportation painted “mile markers” on the highways to assist the CHP pilot in ascertaining the speed of the vehicle. These markers are large white lines that run perpendicular to the solid white emergency lane. You will see these markers shortly after passing the “Patrolled by Aircraft” sign. The pilot utilizes a stop watch to determine your speed from one mile marker to the other. He will then radio down to a waiting CHP officer to make the stop and issue the citation. However, these citations are ILLEGAL in California because the above scenario is considered a speed trap.

Speed traps are illegal in California and pursuant to California Vehicle Code Section 40801 “No peace officer or other person shall use a speed trap in arresting, or participating or assisting in the arrest of any person . . . nor shall any speed trap be used in securing evidence as to the speed of the vehicle.”

A speed trap is defined as a particular section of highway measured as to distance and with boundaries marked, designated, or otherwise determined in order that the speed of a vehicle may be calculated by securing the time it takes the vehicle to travel the known distance. See California Vehicle Code Section 40802(a).

The law goes even farther and prohibits the introduction of evidence if a speed trap was used. Section 40803(a). And the officer is deemed INCOMPETENT as a witness. Section 40804(a).

If you are stopped for speeding, and suspect a CHP aircraft was employed to obtain your speed, you need to take your case to trial.

Furthermore, if you stopped as a result of a speed trap and there are no other vehicle code violations observed, you may be able to suppress any evidence seized as a result of this illegal stop. Therefore, if you are stopped by an officer solely for speed via a speed trap you are eventually arrested for DUI in California, you may be able to suppress the blood alcohol results. Since the officer is deemed incompetent to testify as to your speed, his testimony cannot be considered. Also, California Vehicle Code Section 40808 does not allow the speed trap evidence to come in as the Truth-In-Evidence clause of the California Constitution has been specifically abrogated per 40808.

For further information or assistance, contact the law firm of Wallin & Klarich for assistance. Call us toll free 888-749-0034 and visit our website at

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