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Effectiveness: 4 Star Cost: $$$
Use: Unknown
Time: Medium

In 2021 some 57% of passenger vehicle occupants killed in crashes at nighttime were unrestrained. In contrast, 43% of fatally injured passenger vehicle occupants in daytime crashes were unrestrained (NCSA, 2023c). Several States have experienced smaller gains in seat belt use associated with enforcement campaigns after conducting them for several years (Nichols & Ledingham, 2008). These programs also have been conducted almost exclusively during the daylight hours, and the available data suggest that belt use is lower at night (Chaudhary et al., 2005; Hedlund et al., 2004; Nichols & Ledingham, 2008).

Resources focused on nighttime seat belt enforcement may provide additional gains in seat belt use and injury reduction. In particular, belt law checkpoints, saturation patrols, or enforcement zone operations could be conducted at night, when belt use is lower, DWI is higher, and crash risk is greater than during the day. Enforcement activities should be conducted in locations with adequate lighting or by using light enhancing technologies. The first demonstration of this strategy took place in 2004 in Reading, Pennsylvania (Chaudhary et al., 2005).


There is little information available on how frequently nighttime, high-visibility seat belt law enforcement strategies are used. One demonstration of a nighttime program in Pennsylvania was conducted in 2004 (Chaudhary et al., 2005), another demonstration program involving three North Carolina communities was conducted in 2007 (Solomon, Chaffe, & Preusser, 2009), Washington State conducted a 2-year statewide high-visibility nighttime seat belt enforcement program from May 2007 through May 2009 (Thomas et al., 2010), and Oklahoma, Tennessee, and Maryland conducted enforcement waves from 2011 to 2013 (Nichols, Chaffe, & Solomon, 2016; Retting et al., 2018).


Research has shown that short-term HVE programs are effective at increasing nighttime seat belt use (Boakye et al., 2018; Chaudhary et al., 2005; Retting et al., 2018; Solomon, Chaffe, & Preusser, 2009; Thomas et al., 2017).

A detailed evaluation of a nighttime seat belt enforcement program in Washington State found that it was effective across outcome measures (Thomas et al., 2017). The program used a combination of HVE and both paid and earned media. Public surveys indicated that 70% of motorists reported hearing or seeing campaign messages and noticed increased enforcement. Over the course of the program, observed daytime and nighttime seat belt use levels trended upwards from initially high levels, with a larger increase occurring for nighttime use (from around 95% to 97% at night). Additional time-series analyses of crash data found that the program was associated with 3.4 fewer nighttime fatalities per month, even after accounting for the effects associated with the State adopting primary seat belt enforcement prior to the program. An evaluation of the first year of this Washington program also looked at the characteristics of observed drivers (through self-report, driving, and criminal records) finding notable differences between unrestrained and restrained drivers by time of day (Thomas et al., 2010). For example, unrestrained nighttime drivers were 2.7 times more likely than restrained daytime drivers to have had a felony arrest and 3.0 times more likely to have had an alcohol citation. As part of the outcome evaluation, debriefings with local law enforcement agencies indicated that enforcement personnel felt that the publicity campaign enhanced their efforts and that they would recommend the program to other agencies.

A 3-year high-visibility nighttime seat belt enforcement program conducted in Maryland successfully raised nighttime seat belt use (Retting et al., 2018). This program included five waves of HVE coupled with extensive paid and earned media. The primary message of the ad campaign was: “Cops are cracking down on seat belt violations, especially at night.” Driver awareness of the seat belt enforcement increased significantly during the HVE period. Furthermore, despite the fact that seat belt use rates were already high in this region (90-95%), there was a small but significant increase in observed nighttime seat belt use in three of the five waves when compared to a pre-HVE period. Control sites showed no changes in nighttime belt use across the same timeframe. A similar pattern was observed with unbelted injury crashes at night. These rates dropped at HVE sites when compared to the pre-HVE period and control sites showed no change in crash rates. Like the Washington State program, nighttime unbelted drivers were more likely to have poorer driving records and more prior citations for speeding, negligent/reckless driving, license-related offences, and crashes.


The costs of nighttime high-visibility seat belt law enforcement programs are probably somewhat greater than the costs of programs conducted during daylight hours. In addition to the costs, discussed for Short-Term, High-Visibility Seat Belt Law Enforcement, nighttime programs may entail somewhat higher costs if night-vision technology is used.

Time to implement:

Nighttime high-visibility seat belt law enforcement programs require 4 to 6 months to plan and implement.