ALTHOUGH THE 1967 BRITISH ROAD SAFETY ACT, WHICH AUTHORIZED POLICE TO CONDUCT BREATHALYZER TESTS IN ACCIDENTS AND TRAFFIC VIOLATIONS, HAD AN INITIAL DETERRENT EFFECT, THIS EFFECT HAS VANISHED.
THE LAW WAS ACCOMPANIED BY EXTENSIVE GOVERNMENT-SPONSORED PUBLICITY CAMPAIGNS AND PRESS COVERAGE. CRASH RATES, WHICH DECLINED 15 TO 25 PERCENT IN 1967-1968, STEADILY INCREASED THEREAFTER TO A PEAK 35-PERCENT INCREASE IN 1974. TWO MAJOR FACTORS CITED FOR THE LATER INCREASES WERE AN INCREASING USE OF ALCOHOL AND A GROWING REALIZATION ON THE PART OF DRIVERS THAT ALTHOUGH THE RISK OF DETECTION AND CONVICTION WAS HIGHER THAN BEFORE THE ACT, THE ACTUAL RISK WAS STILL LOW. IN JULY 1975, CONCERN OVER THE GROWING PROBLEM OF DRINKING AND DRIVING IN CHESHIRE LED TO THE IMPLEMENTATION OF A MANDATORY BREATH TEST FOR DRIVERS INVOLVED IN CRASHES OR TRAFFIC VIOLATIONS. A 1-WEEK PRELIMINARY UNPUBLICIZED CAMPAIGN RESULTED IN 38 CONVICTIONS FOR VIOLATIONS OF THE ROAD SAFETY ACT, AS COMPARED TO ONLY 13 DURING THE SAME PERIOD A YEAR PREVIOUSLY, WHEN BREATH TESTS WERE LEFT TO THE OFFICER'S DISCRETION. A SECOND ENFORCEMENT CAMPAIGN WAS IMPLEMENTED SEPTEMBER 1 TO SEPTEMBER 28, 1975. DURING THIS PERIOD NEWS OF THE CAMPAIGN WAS LEAKED TO THE PRESS RESULTING IN CONSIDERABLE PUBLICITY AND ACCOMPANIED WITH POLITICAL CONTROVERSY. DURING THIS SECOND PERIOD, THE NUMBER OF ACCIDENTS WAS REDUCED FROM 153 IN THE COMPARABLE PERIOD OF 1974 TO 94 DURING THE CAMPAIGN, AND FATAL ACCIDENTS WERE REDUCED FROM 13 IN 1974 TO 8 IN 1975. A TIME SERIES ANALYSIS OF DATA FROM APRIL 1974 THROUGH MARCH 1976 SHOWS THE DETERRENCE EFFECT WAS RETRIEVED DURING THE 1-MONTH CAMPAIGN. ANALYSIS OF DATA DURING THE UNPUBLICIZED 1-WEEK TRIAL IN JULY INDICATED NO REDUCTION IN TRAFFIC ACCIDENTS OR FATALITIES. RESULTS INDICATE THAT ENFORCEMENT COUPLED WITH PUBLICITY CAN RESULT IN IMPORTANT AND SIGNIFICANT DETERRENCE EFFECTS. (JAP)