In 2006, Washington’s daytime belt use rate of 96% was one of the highest rates in the nation. Washington’s nighttime fatalities, however, were four times greater than daytime fatalities. The National Highway Traffic Safety Administration (NHTSA) and the Washington Traffic Safety Commission (WTSC) worked together to conduct a statewide high-visibility Nighttime Seat Belt Enforcement (NTSBE) program to address high fatality rates at night. The program followed NHTSA’s basic Click It or Ticket (CIOT) model, but each of the enforcement waves occurred during the nighttime rather than the daytime. This report describes the activities that took place during the two-year NTSBE program and the evaluation of the results. The NTSBE program combined high-visibility enforcement supported by paid and earned media about the enforcement to increase nighttime seat belt use via general deterrence. WTSC developed radio and television advertisements that featured the head of Field Operations for the Washington State Patrol (WSP). The primary message of the ad was that “extra seat belt-focused law enforcement patrols are taking place at night because the death rate at night is four times higher than it is during the day.” Over the two-year project, WTSC spent $1,358,867 on media and received placements valued at an estimated $2,782,253. In addition, 3,876 public service announcement placements were “earned” on TV, radio, and in newspapers. There were five dedicated nighttime enforcement waves — May 2007, October 2007, May 2008, October 2008 and May 2009. The May waves coincided with national Click It or Ticket mobilizations. The program spent $1,594,350 on law enforcement over the two years of the program, and Washington officers issued 20,721 seat belt citations during NTSBE activities. The evaluation activities included public awareness surveys and observations of seat belt use. Public awareness surveys found that the paid media messages and enforcement campaigns successfully delivered the message. Most motorists (70%) surveyed at driver licensing offices across the State reported that they saw and heard the NTSBE messages about increased nighttime enforcement and noticed increased enforcement at night. After each wave, the percentages of survey respondents who said they had read, seen, or heard any media about nighttime time seat belt enforcement increased. There also were large increases in the percentage of survey respondents who said they had noticed increased seat belt enforcement at night. About 8 in 10 young males 18 to 34 years old, the primary high-risk target group, knew about the stepped-up enforcement occurring at night across the State. Day and night observations of seat belt usage occurred at 40 observation sites. Together, the 40 sites produced a belt use rate similar to the statewide daytime use rate. Both day and night belt use started and remained high. Although there was some fluctuation, there was an increasing trend in nighttime and daytime seat belt use over time, but NTSBE had a larger effect on nighttime belt use than on daytime belt use. It was unknown how shifting CIOT resources from daytime to nighttime might affect daytime belt use. However, Washington’s statewide daytime use rate showed essentially no change from 2007 to 2009. The official statewide survey has more than 10 times as many sites as the mini-sample surveys, provides the best representation of daytime seat belt use across the State, and is less prone to error. Belt use remained extremely high whether measured by either the statewide or the 40-site subsample. As part of the first year of NTSBE activities, WTSC conducted officer debriefings with representatives from several of the participating law enforcement agencies to assess how the program was working. One of the sessions included law enforcement personnel from agencies that had not participated in the program. The law enforcement officers supported WTSC’s focus on nighttime seat belt usage even though it was new to many agencies. Law enforcement personnel said that the publicity campaign was critical and enhanced their enforcement efforts. They reported relatively minor operational issues, most of which dealt with the initial mandatory use of a stationary spotter. Officers reported that the stationary spotter was not effective in low volume areas at night, and many agencies began using roving patrols to meet their contact targets for the campaigns. In response to these comments, WTSC relaxed the requirement and permitted grantees more discretion. Officers thought that with minor adjustments and a little more flexibility, the program would continue to be effective in Washington even though daytime seat belt use is already high. Overall, the law enforcement officers said that they would highly recommend the nighttime seat belt program to other law enforcement agencies. Researchers conducted a number of time-series analyses of fatalities from January 1994 to June 2009 to determine NTSBE’s impact. In 1994 Washington’s seat belt law was a secondary enforcement law, changing to primary enforcement on July 1, 2002. The analyses considered the effect of Washington’s primary seat belt enforcement law in 2002 and of the nighttime enforcement program that began in May 2007, and compared Washington to two nearby States and all other primary law States during these periods. Looking at vehicle miles travelled, after primary enforcement went into effect, Washington’s overall occupant fatalities per 100 million VMT were significantly lower when compared to Oregon, California, and all other primary law States. During NTSBE, Washington’s overall occupant fatalities per 100 million VMT were lower but did not reach statistical significance. In other words, the fatality rates of other primary law States were also decreasing during Washington’s NTSBE period. Looking at licensed drivers, after primary enforcement went into effect, Washington’s overall occupant fatalities per 100,000 licensed drivers were significantly lower when compared to Oregon, California, and all other primary law States. During NTSBE, Washington’s overall occupant fatalities per 100,000 licensed drivers were significantly lower when compared to the fatality rates of Oregon and all other primary law States, but the decrease did not reach statistical significance when compared to California. Given that the combined series of all other primary law States is less variable from month-to-month than the individual States, the rest of the analyses used it as the comparison. The series of all other primary law States combined contains a larger number of occupants than the individual States and thus provides more statistical power for the comparisons. There were 2.5 fewer nighttime fatalities per month in Washington after implementation of the primary enforcement belt law and an additional 3.4 fewer nighttime occupant fatalities per month during NTSBE. Similarly, there were 2.1 fewer daytime occupant fatalities per month after primary belt law enforcement, and another 4.1 fewer daytime occupant fatalities per month during the NTSBE. Overall, these results show reductions in total daytime and nighttime occupant fatalities in Washington with both primary enforcement and NTSBE. While the previous analyses looked at total fatalities in Washington, the next question is whether belt use among occupants who were fatally injured increased during either program. For this analysis, an increase in belt use suggests a positive effect for this high-risk group. Belt use among fatally injured Washington occupants at night increased 16.4 percentage points after primary enforcement, but the change was not statistically significant after NTSBE. Daytime belt use among fatally injured occupants, however, was statistically significantly higher after both primary enforcement and NTSBE. These results suggest that both daytime and nighttime belt use among fatally injured occupants increased after passage of primary enforcement, but NTSBE did not produce a statistical significance effect. Washington’s nighttime enforcement strategies could be adapted to other States. Nighttime enforcement is probably not suited for rural areas or areas with low nighttime traffic volume. Nighttime enforcement takes longer per stop and yields more DUI arrests than daytime programs. Future research might focus on applying nighttime enforcement strategies in a primary law State with markedly lower belt use (closer to the national average), a greater difference between daytime and nighttime observed belt use, or in a State in the process of changing from a secondary to a primary. (Author/publisher)
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