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Moving Radar Additions


Many have been hit with moving radar. However some have had problems with what should be an easy defense. Moving radar has serious problems and the following should help. 


First one should have a good understanding as to how the Tipmra works and how one goes about making evidence inadmissible. This section should be considered as an addition to the Standard defense of making the evidence inadmissible.


In the Tipmra we learned that when stationary radar is used the officer is required to do a radar survey. That is he should determine if any outside items can possibly interfere with his reading. The list of items is long and irrelevant to your defense. The important issue is that every radar manual ever published emphases the importance of the radar site survey. The survey does not have to be complicated but it must be preformed. 


In the Tipmra we also learned that the offending vehicle must be identified. To do this stationary radar has a site. The recommended method for officers is to first make a visual estimation that a vehicle is speeding and then aim the radar gun at that vehicle to determine its speed. If there are two or three vehicles together it is not possible to determine the speed of a specific vehicle as the radar beam is not selective as in laser.


(There is no such thing as moving laser for speeding). 


Moving radar uses two beams. One to determine the officer’s car speed and the other to determine the relative speed at which your car is approaching the officer’s car. It then subtracts the relative speed from his speed to determine your speed. His radar gun takes the return beat frequency ground shadow return in front of him and if the antenna is misaligned a cosine error is encountered. Objects such as Bridges or Structures on the side of the road can also produce a return further increasing the cosine error.


Cosine error. This deals with the angle from which a reading is taken to relative motion. The stationary objects on the officers side are always at an angle to his motion. The further the object is from the side of the road, the greater his cosine error. The greater the cosine error the slower his speed will read. The slower his speed reads from his actual speed the greater the difference he reads as you your speed. In simple terms, the greater the cosine error the higher your speed will read on his device. This error is significant and can cause reading of 10 to 30 miles greater then the speed you are actually doing. I stationary radar the cosine error works in favor of the driver. In moving radar it works against the driver yielding a higher speed.


I suggest that if you want more definitive information you can find it at  . This site is the worlds best as to available scientific information as to how radar works and what is in the radar hand books officers have.


The officer and his device have no method of determining the cosine error and correcting for it. This is because the officer’s vehicle is moving and always taking different readings for different objects. The unit can not determine the angle or the distance at which the object is because all it receives is a “Beat Frequency Oscillation” which it converts to a speed.


The officer has the unit placed on the dash. He can not look through a targeting device to determine which vehicle the unit is looking at and which vehicle is producing the speed reading. If you are the only car on the road he can justifiably say that you were the targeted vehicle. If there is more then one vehicle he can not determine which vehicle is giving him the reading.


As you can see moving radar has serious problems. It is because of these problems that moving radar has never had Judicial Notice taken in any jurisdiction in The USA or Canada.


In Our special situation Judicial Notice is when a hearing was held where competent scientific information was presented and examined and it was determined that the science is sound and that the device seeking Judicial Notice is accurate to a legal degree of certainty. For example all Jurisdictions have taken Judicial Notice that stationary radar when properly calibrated and operated by a trained person at a site that has had a radar survey done is accurate to a legal degree of certainty. For Stationary radar this goes back to court cases in the 1960’s where competent scientific evidence was presented. Because of Judicial Notice the court no longer has to prove that Stationary radar works.


This is not the situation with moving radar. As you know by now, moving radar has serious problems that scientifically can not be overcome. Simply by moving it is in an ever changing environment to which no legal degree of certainty can be established. As such no Judicial Notice exists. (there are a few isolated instances however it is doubtful that you are being tried in a jurisdiction where such notice exists. Even then it is doubtful that the prosecution has any knowledge abut any such case to bring to the attention of the court. In other words proceed with the assertion that no judicial notice exists. Let them prove Judicial Notice.)


I know, the question you have is “If there is no Judicial Notice, why are people convicted and why do they list moving radar on a pre-printed ticket for the officer to place a check mark”? This is because unless you object to something the court assumes that you accept it! In other words if you don’t object to Moving radar evidence being entered against you the court takes the legal assumption that you accept the accuracy of the readings of the device.


Now let’s put this all together for trial. You start as the Tipmra suggests by presenting your case law to the Judge for him to read or ignore. The important thing is you presented case law. The Officer will be questioned and when the question comes up or the officer starts to testify to using moving radar you immediately object. ( With the very first mention of the word “MOVING RADAR” OBJECT!!!)

 I suggest you copy and read the objection as written here.

“I Object, Ample Judicial notice exists as to the accuracy of stationary radar where the unit has been properly calibrated, operated by a trained person and a radar site survey has been preformed. This is not stationary radar, but moving radar and No Jurisdiction in this country has ever taken Judicial Notice that moving radar is accurate to the legal degree of certainty necessary for a conviction of a speeding offense. The reason such Judicial Notice does not exist is because scientific evidence as to the accuracy and reliability of moving radar has never been shown to be sufficient as to the accuracy reliability and admissibility of evidence obtained from such a device. Judicial notice does not exist and unless expert scientific testimony is presented, and examined as to the accuracy of this specific device I object to any evidence from this device being admitted or even considered.”


 At this point the Judge or Magistrate or whoever is trying the case will do one of the following. 


  • He will ask you to present some document or determination that moving radar has no judicial notice. “Your Honor, Since none exists it is not possible for the defense to present something that does not exist. The Burdon is on the prosecution to show that Judicial Notice exists if it intends to enter into evidence obtained from moving radar.”
  • He may say. “I will take Judicial Notice”. You say “In that event your Honor, please let the record show that you are taking personal Judicial Notice as to the accuracy of a device to which no scientific evidence as to it’s accuracy is  presented and no Judicial Notice to such accuracy exists where such scientific evidence has been presented and examined by a court of competent Jurisdiction. Let the record further show that Defendant objects to this evidence being entered and that the prosecution has not presented prior Judicial Notice or scientific evidence as to the accuracy of the device used.”
  • He may say “Proceed” without addressing the issue of Judicial Notice. You say “Your Honor, let the record show that you are allowing evidence to be admitted from a device to which no Judicial Notice as to it’s accuracy exists and no competent scientific evidence is being presented.”
  • He may dismiss the case right there.


if the trial continues, let the officer finish testifying and then on cross examination ask him these questions. Proceed with the standard Tipmra defense first concerning the testing of the device. If you don’t get the case dismissed by this point, move on to this next line of questioning.


Remember you can ask leading questions on cross examination. The prosecutor may object as to your questions on occasion to get you off balance. Say “Your Honor, this is cross examination and leading questions are permissible, Federal Rules of Evidence 611-(c)”.


Q1. Moving RADAR Angular Effect: Officer what is moving RADAR angular effect and how can it result in a speed reading that is higher then the vehicles actual speed? (These can produce a lower-than-actual patrol speed measurement and thus a higher-then-actual target speed calculation. The cosine error and can be caused by a incorrect antenna angle or lateral displacement of stationary objects.”


Q2. PATROL SPEED SHADOW EFFECT. Officer what is PATROL SPEED SHADOW EFFECT? (Remember that moving RADAR depends on two speed-readings, that of the target and that of the patrol.  A shadow effect may be caused if the beam that is supposed to determine the patrol car speed by tracking stationary terrain instead locks onto a large moving vehicle in front of the patrol car.  This large vehicle (usually a truck) must be close enough to the RADAR unit to effectively reflect a major portion of the normal beam.  If this occurs, the patrol car’s speed will be displayed as the difference in speeds between the patrol car and the truck rather than the patrol car and the stationary terrain.  If a target vehicle is approaching at this time, the RADAR could add the remainder of the patrol car’s speed to the target’s speed.  (TARGET SPEED = CLOSING SPEED – PATROL SPEED.) 

Then ask the follow up. Officer did you make note of the Truck that was a short distance in front of you or was your attention focused on the radar readings and my vehicle? 


Q3. BATCHING EFFECT: Officer, what is BATCHING EFFECT? (The Batching effect may occur if the patrol car is rapidly changing its speed while the RADAR speed measurements are being made.  Some RADAR counting units may be unable to keep up with the rapidly changing speeds.  Instead of using the true speed of the patrol car to measure closing speed, the counting unit may use the speed that the patrol car was traveling a few fractions of a second earlier.  If the patrol car is rapidly accelerating, then its earlier speed was lower than its present true speed, and the target speed calculation may be higher than the target’s true speed.) 


Q4. PATROL SPEED VERIFICATION (MOVING RADAR ONLY): Officer what type of speed verification was used on the day of my arrest? “Current moving RADARs, as previously noted, possess not only a target-vehicle, speed display window but also a patrol-car, speed display window.  The patrol speed indicated on the RADAR must correspond with the reading on the patrol vehicle’s speedometer, which must be certified as well.  This verification ensures that the RADAR computation of the target speed is based on a valid patrol car speed.  This additional element has been mandated by case law for moving RADAR and is considered essential for a valid moving radar case.” 


Follow up question: Officer please present documentation as to the last time the speedometer on the car used was calibrated and certified. 


Q5. Harmonics interference: “Officer what is Harmonics interference” (The first source of interference, harmonics, refers to Radar’s tendency to occasionally process the wrong radio frequency.  Harmonics may include radio energy released by airport RADAR, mercury vapor and neon lights, high-tension power lines, high-output microwave transmission towers, and transmissions from CB and police radios.) 


Q6. Acceleration Error: Officer what is acceleration error or deceleration error? (if the officer is accelerating his speed computations will be from a lower speed for his car resulting in a higher speed for your car because the speed when the return comes in and is calculated is not the speed which the car was before the computation.) 


Moving Radar Variables: Target speed will only measure higher than true speed when the target is approaching the patrol car AND the cosine angle between radar and target are small, (typically less than 5%) AND the angle between the patrol car and the ground is large, (typically greater than 5%). Patrol car and target speeds are significant, patrol car speed greater than target speed increases the error. (The greater the difference the larger the error and the higher the measured speed).

Should the officer say something to the effect that he does not know about this or that he is not required to know the technical workings of police radar then ask this. 


Officer these effects are listed in your radar hand book isn’t that correct?  He will say either yes, no or I don’t know. If he says yes but does not know what it is you can assert to the court that he has not been properly trained as it can be assumed that a properly trained person would know what it is. If he says no then say “ Officer Jones every radar handbook details these items, are you saying no because you didn’t read the handbook or because you forgot what is in the handbook”?  If he says he does not know then ask the court for dismissal as the officer obviously ahs not had proper training. 


The Final Cope de Grass: 


In stationary radar the officer targets you with his radar gun. By targeting you he can reasonably (not always) assert that your vehicle was the one targeted and the speed reading was from your vehicle. I moving radar he can’t make that assertion because the unit is mounted in the car and he has no idea as to which vehicle is targeted. 


Q1a. Officer when you use stationary radar do you target a vehicle with the unit or do you just aim it in any old direction and then pick out a vehicle at random to ticket? “ he will say that he targets a vehicle and that the vehicle he targets is the one giving the reading. 

Q2a. In other words officer you aim the radar gun at the vehicle, you have a sighting device on the radar gun and the vehicle in the radar guns sights is the one to which the speed reading belongs, is that not correct? ( he will say yes ) 


Q3a. Officer the radar unit you used for moving radar is it affixed in a stationary or permanent position on your car or do you drive with one hand and target vehicles holding the radar gun with the other hand as you are driving? (The answer is obvious) 


Q4a.  Officer since you were not looking down the line of site on the radar gun how can you determine which vehicle was giving the reading. (He either will say your vehicle appeared to be the fastest or that it only picks up the first vehicles speed or fastest vehicles speed.) 


Q5a. Officer You don’t know which vehicle was giving the reading and you are just assuming that my vehicle was the one, isn’t that correct”?


He may say No he was not assuming anything and that it was your vehicle that was giving the reading. In that event ask more questions as you think of them to show that he had no reasonable way without sighting down his radar gun to determine that your were the vehicle causing the readings.


Closing Arguments: Refer to the fact that there is no Judicial notice and that this case, simple as it is shows why no Jurisdiction has ever given Judicial notice. Explain that unlike stationary radar which has judicial notice moving radar has problems that have not been overcome. This includes the inability to positively identify the vehicle causing the reading. The fact that since the officers vehicle is moving no radar site survey for interference is possible and the officer has no way of knowing what interference is occurring. The fact that the accuracy of the officers own vehicle speed is essential and if he is accelerating or slowing down the unit will not give a correct reading. The cosine error is a problem to which no correction is possible as that neither the officer or the unit knows that angular factor of the stationary object giving the internal reading for the speed of the officers car. Anything else that you can think of. 

Outline that Tipmra items and finish off by stating that the best the prosecution has shown is a guess and accusation with no verifiable substance and as such does not rise to the degree of evidence necessary for a conviction.


In Today's World a Radar Jammer Radar Detector is essential to prevent tickets  Radar Detector/Jammer





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