Background of Police Radar by NHTSA

U.S. Department of Transportation

National Highway Traffic Safety Administration

(Background Discussion)

Issue: The use of police traffic radar has become widespread throughout the United States and, until recently, was widely accepted by the courts and the general public as a reliable and accurate means of measuring vehicle speeds. However, recent technological advances, especially the development of “moving radar,” have altered the basic concepts initially accepted by the courts. These technical innovations have resulted in increased and highly publicized challenges to both the reliability and accuracy of modern traffic radar devices and the adequacy of police radar operator training.

Discussion: Police traffic radar has been used to detect speeding motorists for about 30 years in this country. During that time radar speed measuring devices have evolved from the original bulky stationary models to the present compact and sophisticated models capable of monitoring vehicle speeds in both stationary and moving modes. These technological advances have greatly enhanced the mobility, efficiency and effectiveness of police traffic radar operations. However, highway safety and traffic law enforcement officials are now faced with a dilemma since the same technological advances that enable increased productivity and efficiency have resulted in increased scrutiny by the courts. In addition, the public is now beginning to question both the reliability and accuracy of radar devices and the adequacy of police radar operator training.

At the present time there are no nationally recognized performance standards for police traffic radar speed measuring devices. Further, operator training requirements, which have traditionally been established by each individual police agency (usually with the assistance of the radar manufacturer), range from less than one hour to several days. The quality of operator training often has not kept up with the technological advances. In many cases, training has been limited to teaching the officer how to set up, test and operate the device. All too often, failure to provide detailed training in recognizing and avoiding the electronic anomalies associated with modern traffic radar devices has led police officers to believe that radar devices are infallible.

A highly publicized Dade County, Florida evidentiary hearing regarding the reliability and accuracy of radar illustrates the type of challenge now being encountered. The hearing, conducted by Judge Alfred Nesbitt in April 1979, focused on two issues. First, whether radar speed measuring devices currently produced are reliable enough to be used as evidence; and second, whether police officers are receiving adequate training in the proper operation of the devices. After nine days of testimony, during which experts from both sides were invited to give testimony, Judge Nesbitt ruled:

…that the reliability of the radar speed measuring devices as used in their present modes and particularly in these cases, has not been established beyond and to the exclusion of every reasonable doubt ….

While the Dade County hearing has not triggered the predicted nationwide demise of police traffic radar, it has highlighted the fact that in certain circumstances radar does have its limitations. Subsequent court decisions such as State of New Jersey vs. Wojtkowiak and State of Hawaii vs. Earl W. Fedje, et al., generally have upheld the reliability and accuracy of police traffic radar. However, the message from the courts is clear: highway safety and law enforcement administrators must ensure that radar operators receive adequate training, including recognition and avoidance of the electronic anomalies associated with such devices. Operators must be able to demonstrate their competence with the unit under varying conditions in supervised field performance tests. In addition, the radar manufacturing industry must implement strict quality control measures to ensure the reliability and accuracy of their equipment, and continue to search for ways to improve the target identification capabilities of present radar devices.

The courts, as well as some radar critics, also have pointed out the need for State-level policy guidance for police radar enforcement programs. The immediate reaction to such criticism tends to be defensive. Perhaps this is an appropriate time to review radar programs from a constructive viewpoint. After evaluation of present programs, highway safety and law enforcement officials should develop and implement comprehensive policies and procedures to ensure that police traffic radar is used properly and that traffic safety and energy conservation goals are achieved. State-level policy guidance would provide the added benefit of increased uniformity within a State and encourage statewide development of standard operating procedures. This would enhance voluntary compliance as the motorist travels through the many jurisdictions within each State.

The National Highway Traffic Safety Administration (NHTSA) is sponsoring two programs which should upgrade both the reliability and credibility of police traffic radar equipment and the quality of operator training.

Equipment: In August 1977, before many of the above issues were raised publicly, we entered into an interagency agreement with the National Bureau of Standards (NBS) in the Department of Commerce to develop performance standards for police speed measuring devices. The NBS has inventoried all police speed measuring devices (radar and nonradar) used in this country and is in the process of developing comprehensive performance standards for each speed measuring device category. The performance standards for radar devices should be completed by June 1980. Once the standards are established, NBS will coordinate the testing of existing devices and compile a list of those devices meeting the standards. This qualified products list will be published in the Federal Register.

The qualified products list will aid police administrators in making more informed purchasing decisions. Moreover, the list will identify those specific models which can be purchased by State and local law enforcement agencies with Federal highway safety funds.

In addition, we asked NBS to conduct special performance tests on the six radar devices identified in the Dade County hearing. The purpose of this project was to test each of the six radar units to observe their operational capability in certain operating situations or environments that were described in the hearings The preliminary test results confirm that the six devices produced reliable and accurate speed measurements. However, NBS also determined that there are certain operational situations which may lead an inattentive or untrained operator to obtain an inaccurate reading or to associate the speed indicated on the radar device with the wrong vehicle. NBS also points out the potential for obtaining an erroneous reading on a target vehicle under certain conditions when the radar unit is operated in the moving mode. Judgemental errors may occur if police radar operators do not understand and avoid the specific circumstances which give rise to these anomalies.

It is also clear that police administrators must ensure that radar devices are properly maintained and periodically tested and calibrated. Written policy defining maintenance and calibration procedures should be established in each agency. The procedures should define the conditions under which each device should be calibrated by a licensed technician.

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The written policy should specify that accurate maintenance, repair and calibration records for each device should be established and maintained by the agency. These records should be available to the courts, whenever necessary, to verify the accuracy of the device.

Training: In September 1978, we awarded a contract for development of a model training program for police officers in the use of speed measurement devices. The training program has two elements, one covering radar speed measuring devices and one covering non-radar devices. The overall goal of the training program is to improve the effectiveness of speed enforcement through the proper and efficient use of speed measurement devices. The specific objectives of the radar course are to develop and/or improve the trainee’s ability to:

  • Describe the association between excessive speed and accidents, deaths and injuries and describe the highway safety benefits of effective speed control
  • Describe the basic principles of radar speed measurement
  • Acquire and demonstrate basic skills in testing and operating the specific radar instruments
  • Identify the specific radar instruments used by the trainee’s agency and describe the instruments major components and their functions
  • Identify and describe the laws, court rulings, regulations, policies and procedures affecting radar speed measurement and speed enforcement in general
  • Acquire and demonstrate basic skills in preparing and presenting records and courtroom testimony relating to radar speed measurement and enforcement

The radar training course is designed in a modular format to provide maximum flexibility for the user. It is comprised of eight units, each of which has specific performance objectives. The formal classroom training comprises a block of 24 instruction hours. Upon successful completion of a written exam, the trainee must undergo a minimum of 16 instruction hours of supervised field practice. After completing the course of instruction, the trainee must be able to demonstrate his operational (real world) competency before being certified to take enforcement action based on radar speed evidence. Recertification of all operators should occur within not less than one nor more than three years.

Although this course focuses on enforcement and is intended primarily for the police patrol officer, we recommend participation in the training program by traffic adjudication personnel, e.g., judges, administrative hearing officers, prosecutors, etc. Such personnel routinely decide upon the admissibility and weight of radar speed evidence, the strengths and weaknesses of the instruments and the capabilities and limitations of the operators. This type of training will provide adjudication personnel with a good working knowledge of radar speed measurement principles and an understanding of the issues relevant to judicial deliberations.

Position: The National Highway Traffic Safety Administration believes that police traffic radar is an effective enforcement tool. The role of police traffic radar in traffic safety enforcement continues to be of critical importance, especially in view of the safety and fuel conservation benefits of the 55 mph speed limit and the requirement that all States must meet uniform national compliance criteria enacted by Congress. Police traffic radar provides a means of increasing enforcement effectiveness and thus enables police administrators to better cope with the scarcity of manpower resources and rapidly increasing fuel costs.

Highway safety and law enforcement officials should recognize the fallacy of purchasing radar devices solely on the basis of economy without due regard to their performance capabilities. These officials must also recognize the importance of greatly improved operator training and State-level policy guidance to ensure high quality and more uniform police radar operations throughout a State. Inaction on these issues by State and local highway safety and law enforcement officials may well result in judicial limitations governing the use of police traffic radar. It is essential that each State develop a comprehensive radar speed enforcement program which, as a minimum, embraces equipment standards, operator training, operator certification, and policy/procedural guidance. Accordingly, each State is strongly urged to:

  • Adopt the forthcoming NBS/NHTSA radar speed measuring device performance standards and require police agencies to purchase devices meeting those standards
  • Develop policy guidelines to ensure that radar speed measuring devices receive proper care and upkeep and establish clear procedures for programed maintenance, testing, and calibration
  • Ensure that adequate maintenance and calibration record systems (suitable for introduction as evidence in court) are developed and maintained by each agency using radar speed measuring devices
  • Adopt the NHTSA radar operator training program or its equivalent as the statewide minimum training standard
  • Develop a comprehensive State-level radar operator certification program and provide for periodic recertification (every 1-3 years)
  • Develop police radar workshops and seminars for traffic adjudication personnel
  • Establish State-level policy/procedural guidelines to ensure proper use of police traffic radar in meeting traffic safety and energy conservation goals and objectives.

Implementation of these minimal measures should result in significantly improved and more uniform radar speed enforcement programs both within the individual States and nationwide. Their implementation is necessary to establish a sound legal foundation for radar speed evidence and to restore public and judicial confidence in radar enforcement programs.