Admissibility of Motor Vehicle Speed Readings Produced by LTI Marksman 20-20 Laser Speed Detection System, Matter of

• Decision Date: 20 March 1998
• Citation: 714 A.2d 381,314 N.J.Super. 233
• Parties: In the Matter of the ADMISSIBILITY OF MOTOR VEHICLE SPEED READINGS PRODUCED BY the LTI MARKSMAN 20-20 LASER SPEED DETECTION SYSTEM. (Criminal), Morris County
• Court: New Jersey Superior Court

Page 233

314 N.J.Super. 233

714 A.2d 381

In the Matter of the ADMISSIBILITY OF MOTOR VEHICLE SPEED READINGS PRODUCED BY the LTI MARKSMAN 20-20 LASER SPEED DETECTION SYSTEM.

Superior Court of New Jersey,

Law Division,

(Criminal),

Morris County.

Decided March 20, 1998.

Michael M. Rubbinaccio, Butler, for the State

Steven K. Greene, Joseph T. Maccarone and Sohail Mohammed, appeared as Amici Curiae.

STANTON, A.J.S.C.

BACKGROUND

This supplementary proceeding involves the reliability of a device known as the LTI Marksman 20-20 Laser Speed Detection System manufactured by Laser Technology, Inc. For ease of expression, I shall hereafter usually refer to this device as the "laser speed detector" or the "detector." The laser speed detector is a compact, hand-held device which the New Jersey State Police desire to use in enforcing the laws regulating motor vehicle speeds.

In 1996, in connection with a number of motor vehicle speeding cases which were then pending in the municipal courts of Rockaway On June 13, 1996, I issued a written opinion in that matter which concluded that the general concept of using lasers to measure speed is widely accepted in the relevant scientific community and is valid. However, I was not satisfied that it had been proven that the laser speed detector device was accurate and reliable enough to be used for law enforcement purposes. My principal reason for not accepting the laser speed detector was that there had not been, in my view, adequate operational testing of the laser speed detector under actual highway conditions. My view was that good performance testing might conceivably put us in a position of being sure that the detector in fact worked reliably.

Township and Parsippany-Troy Hills Township, I conducted an extensive evidentiary hearing in the Superior Court for Morris County on the admissibility of speed readings obtained by the New Jersey State Police through use of the laser speed detector. In that earlier proceeding, Michael M. Rubbinaccio, Esq., who was then serving as the Municipal Prosecutor for both Rockaway Township and Parsippany-Troy Hills Township appeared for the State. Stephen K. Greene, Esq., Joseph T. Maccarone, Esq. and Sohail Mohammed, Esq. appeared as attorneys for various defendants in the motor vehicle cases then pending in the municipal court.

I suggested that it would be relatively easy to design performance tests which would let independent observers know how accurate the laser detector device was. I suggested that the tests should include vehicles of varying sizes and shapes, that they be conducted under various conditions of traffic flow along actual highways and roads, and that they be conducted at different times of day under varying climatic conditions. I noted that such tests should involve target vehicles whose speed was reliably established either by controlling the driver of the vehicle or through simultaneous measurement of its speed by a reliable device other than the laser speed detector. I further noted that the test data The State did not take an appeal from my decision excluding evidence generated by the laser speed detector. The various cases then pending in the municipal courts were resolved without the use of laser speed detector evidence. However, the State did attempt to conduct performance testing of the detector in an effort to develop data which would permit a reexamination of the admissibility of speed readings produced by the detector. Accordingly, the New Jersey Department of Transportation, Bureau of Transportation Data Development, in cooperation with the New Jersey State Police, Division of Highway Traffic Safety, conducted field testing of the laser speed detector during September, October and November of 1996 and June and July of 1997. Closed track testing of the detector was conducted on September 19, 1996.

would have to be accurately recorded and reproduced for examination, analysis and replication by other persons and agencies.

In 1997, the State moved to have me reopen the evidentiary proceedings involving the laser speed detector. By that time, the pending motor vehicle cases had been resolved and there were no defendants who had an interest in contesting the admissibility of readings from the detector. However, in view of the fact that the State Police were interested in using the detector and were prepared to attempt to justify the admissibility of readings produced by the detector on the basis of the field testing which had occurred, it seemed to me that it would be desirable for any proceeding to take place in this court in a way which would allow the parties to build upon evidence which had been presented during the 1996 hearings before me. Although I thought it useful and in the public interest to try to build on the earlier proceedings, I did not want to have a non-adversarial proceeding before me because such a proceeding would not be likely to produce an appropriately vigorous scrutiny of the data presented.

Fortunately, Mr. Greene, Mr. Maccarone and Mr. Mohammed, attorneys who had represented defendants in the earlier proceedings, remained interested in the issues involved and they agreed to appear as amici curiae and to present evidence and argument I refer to the Opinion which I issued on June 13, 1996 for a detailed description of the laser speed detector and of the operational and conceptual objections which were raised in opposition to its acceptance. I incorporate herein by reference everything which I said in that earlier opinion without repeating it in detail. However, I do think it useful to repeat at this point a general description of the way in which the laser speed detector is supposed to work:

designed to subject any data presented by the State to meaningful scrutiny. Although Mr. Greene, Mr. Maccarone and Mr. Mohammed consented to act as friends of the court on an uncompensated basis, I did enter an order on July 8, 1997, requiring the State to cover the reimbursement of defense expert fees and costs. In this way, we were able to make it possible to evaluate the test data generated by the State on an adversarial basis.

A laser is an artificially generated and amplified light which is in the infrared light section of the electromagnetic wave spectrum. It is not visible to the naked eye. It is very concentrated. The laser speed detector fires a series of laser pulses at a selected remote target. When the laser light strikes the target, a portion of the light is reflected back to the detector. Since the speed of light is a known constant, by measuring the time it takes for the laser pulse to travel to the target and back, the detector is able to calculate the distance between the detector and the target. Each laser pulse which is fired and reflected back establishes one distance reading. The laser speed detector fires 43 laser pulses every time the trigger on the detector is squeezed. These 43 pulses are fired in a total period of approximately one-third of a second. If the target at which the laser pulses are fired is a stationary target, each of the 43 pulses will give the same distance reading to the target, and distance will be the only thing that the detector can tell us about the target. However, if the target is moving, each of the 43 pulses will give a slightly different distance reading and the detector can then compute the velocity or speed of the target from the changes in distance divided by the known elapsed time between the firing of each of the laser pulses. In simplest terms, this is the basic theory underlying the use of lasers to calculate speed, and there can be no dispute about its fundamental validity.

THE STANDARD

In February, 1995, the National Highway Traffic Safety Administration of the United States Department of Transportation issued Model Minimum Performance Specifications for Lidar Speed Measurement Devices. The laser speed detector is a lidar

device. The specifications require that the speed measurements produced by the device shall not exceed true speed by more than one mile per hour or underreport speed by more than two miles per hour. True speed is a somewhat philosophical concept, since any measuring device is susceptible to some amount of error. For practical purposes, the inquiry into whether a particular device meets the standard specified has to be determined by comparing the device in question to other devices whose reliability is generally accepted. Since we are dealing in speed law enforcement cases with efforts to convict motorists of speeding violations, the more significant aspect of the standard is that we do not want a device to over-report speed by more than one mile per hour.

CLOSED TRACK TESTING

Closed track testing of the laser speed detector was conducted at Raceway Park in Englishtown on September 19, 1996. Four standard passenger automobiles supplied by the State Police were driven on the track on controlled speed ranges varying from 90 miles to 20 miles per hour. The vehicles were clocked simultaneously by the track timer, by K-55 radar, by a device known as the PEEK 241 recorder and by the laser speed detector. The track timer used was a Compulink System III which used infrared detectors designed to calculate miles per hour over a 66-foot speed trap. It is certified by various international automobile racing organizations. K-55 radar is widely used by police departments throughout New Jersey for law enforcement purposes and has been accepted as reliable by New Jersey courts for more than 18 years. The PEEK 241 recorder is a portable traffic monitoring device which is used in New Jersey and in many other states by state highway departments to determine traffic volumes and speeds. It is not used for law enforcement purposes against individual motorists. It determines vehicle speed by calculating the time required for a vehicle to activate two road hoses placed a known distance apart.

In the closed track testing at Raceway...