NCJ Number
59672
Journal
Police Magazine Volume: 2 Issue: 5 Dated: (SEPTEMBER 1979) Pages: 22-27,30-32
Date Published
1979
Length
8 pages
Annotation
THE DEVELOPMENT OF POLICE RADAR EQUIPMENT IS HIGHLIGHTED IN LIGHT OF RECENT COURT CASES QUESTIONING ITS ACCURACY AND RELIABILITY.
Abstract
POLICE RADAR WAS DEVELOPED IN 1948 AND, DURING THE 1950'S, CAME TO BE CONSIDERED VALID EVIDENCE FOR ISSUING SPEEDING SUMMONSES. ALL SPEED RADARS PERFORM ON THE SAME PRINCIPLE--THE DOPPLER SHIFT--WHICH POSTULATES THAT THERE IS A STRICT, MATHEMATICAL RELATIONSHIP BETWEEN THE RELATIVE SPEED OF A MOVING OBJECT AND THE OBSERVED FREQUENCY OF SOUND WAVES EMANATING FROM IT. CURRENTLY, THE VALIDITY OF THE DOPPLER PRINCIPLE (OR THE NOTION THAT MODERN EQUIPMENT, WHEN OPERATED UNDER THE BEST POSSIBLE CONDITIONS, CAN ACCURATELY GAUGE THE SPEED OF AN OBJECT EVEN TO A FRACTION OF A MILE PER HOUR) IS NOT BEING QUESTIONED. HOWEVER, THE COURTS ARE CONCERNED AS TO WHETHER RADAR SPEED READINGS CAN BE DISTORTED BY EXTERNAL INFLUENCES, OR WHETHER HUMAN ERROR CAN CONFUSE SPURIOUS READINGS WITH REAL ONES. IN MAY 1979, A DADE COUNTY, FLA., JUDGE SOLICITED TESTIMONY FROM EXPERTS ON OPPOSING SIDES OF THE ISSUE AND RULED THAT RADAR EVIDENCE IN 80 SPEEDING CASES BEFORE HIM WAS INADMISSIBLE BECAUSE THE RELIABILITY OF THE DEVICES WAS NOT ESTABLISHED BEYOND A A REASONABLE DOUBT. IN 1978, THE WISCONSIN SUPREME COURT RULED IN WISCONSIN V. HANSON, THAT STATE COURTS WILL NOT TAKE JUDICIAL NOTICE (A STATUS ACCORDED MATTERS THAT REQUIRE NO PROOF) OF THE ACCURACY OF EVIDENCE OBTAINED BY RADAR AND ISSUED A SET OF GUIDELINES TO HELP TRIAL COURTS DECIDE WHEN AND HOW TO ADMIT RADAR EVIDENCE. SUCH RULINGS HAVE CHALLENGED POLICE EQUIPMENT AND THEIR ABILITY TO USE IT PROPERLY, ENCOURAGING MOTORISTS FACING SPEEDING SUMMONSES TO CHALLENGE TICKETS BY CALLING RADAR EVIDENCE INTO QUESTION. TO ESTABLISH A QUALIFIED-PRODUCT LIST OF RADAR DEVICES, THE LAW ENFORCEMENT STANDARDS LABORATORY OF THE U.S. BUREAU OF STANDARDS IS CONDUCTING A STUDY OF SUCH DEVICES. EQUIPMENT MEETING THE STANDARDS WILL BE LISTED IN THE FEDERAL REGISTER, WHICH WILL INFORM POLICE AGENCIES WHICH DEVICES CAN BE PURCHASED WITH FEDERAL MATCHING FUNDS. LEADING OPPONENTS OF RADAR SAY ITS INACCURACIES MAY RESULT FROM THE NATURE AND RANGE OF THE RADAR BEAM TRANSMITTED FROM THE DEVICE OR FROM A RADIO TRANSMITTER OR RADAR ANTENNA OPERATING TOO CLOSELY TO THE RADAR CONSOLE. CRITICISMS OF THESE DEVICES CONCERNING THE INABILITY OF POLICE OFFICERS TO BE PRECISELY SURE THEY ARE TARGETING THE RIGHT VEHICLE, ARE MET BY POLICE OBJECTIONS THAT EXPERIENCE HAS TAUGHT THEM HOW TO DISTINGUISH CORRECTLY AMONG THE NEAREST, LARGEST, AND FASTEST VEHICLES IN THE RANGE OF THEIR RADAR SETS. FURTHER CONTENTIONS CONCERNING THE RELIABILITY OF RADAR EQUIPMENT ARE PROVIDED. SEVERAL ILLUSTRATIONS ARE USED. (WJR)