U.S. Department of Transportation

National Highway Traffic Safety Administration

1200 New Jersey Avenue SE., Washington, DC 20590

TRAFFIC TECH

Technology Transfer Series

Number 396 September 2010

Year 1 of the Washington Nighttime Seat Belt 

Enforcement Program

As seat belt use has increased, the strong suspicion has arisen

that “residual drivers” who resist buckling up are different from those who have responded to laws, enforcement,

and education by becoming regular belt users. It has been

suspected that the unbuckled are more likely to be driving

at night, to drive after drinking, and to be worse drivers in

terms of crash and violation history than drivers who wear

their seat belts. The National Highway Traffic Safety Administration and the Washington Traffic Safety Commission

(WTSC) joined together to conduct a high-visibility nighttime seat belt enforcement (NTSBE) program in Washington

State to investigate these questions. WTSC’s program follows the basic Click It or Ticket (CIOT) model -- highly visible

enforcement combined with paid and earned media about

the enforcement and evaluation. The emphasis occurred during nighttime to address nighttime crash problems.

For example, from 2001 through 2007, half (49%) of the fatal

crashes in Washington State occurred between 6 a.m. and

5:59 p.m. (daytime) when an estimated 80% of traffic occurs.

Half (51%) of the fatal crashes occurred between 6 p.m. and

5:59 a.m. (nighttime) when about 20% of all vehicle travel

occurs. Washington State has one of the highest seat belt use

rates in the country with about 95% of drivers observed to be

wearing seat belts during the daytime. Despite the high seat

belt use rate, unbuckled motorists accounted for almost half

of the traffic fatalities in the State.

The first year of the Washington nighttime belt program

ran from May 2007 through May 2008. During this period,

WTSC ran three, two-week nighttime seat belt enforcement

campaigns. 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.” Preliminary findings from the first year of the program are now available.

Law enforcement issued 4,516 seat belt citations during

NTSBE activities in May 2007, 3,822 in November 2007,

and 5,194 in May 2008. The number of citations issued per

hour worked was comparable to daytime CIOT campaigns

although fewer law enforcement agencies participated in the

nighttime programs. Other arrests, such as DUI, drug, and

felony arrests per officer hour worked, increased during the

nighttime seatbelt enforcement campaigns compared to daytime CIOT.

Observed Seat Belt Use Increases 

There were statistically significant increases in nighttime seat

belt use at 40 sites across Washington State, selected as a convenience sample that when taken all together, approximate

statewide belt rates. Nighttime belt use started at 94.6%,

peaked at 96.6% in September 2007, and ended at 95.7% in

June 2008. Observed daytime belt use dipped slightly at the

40 sites used in this study, but showed a small increase from

95.5

94.0

94.5

95.0

95.5

96.0

96.5

97.0

May-07 Jun-07 Jul-07

Night Day

Daytime and Nighttime Observed Seat Belt Use at 

40 Sites in Washington

Months of Observations

Sep-07 Nov-07 May-08 Jun-08

Percent Positive Response
TRAFFIC TECH is a publication to disseminate information about

traffic safety programs, including evaluations, innovative programs, and new publications. Feel free to copy it as you wish. If you

would like to receive a copy, contact Angela H. Eichelberger, Ph.D.,

Editor, fax 202-366-7394, e-mail: angela.eichelberger@dot.gov.

1200 New Jersey Avenue SE., NTI-132

Washington, DC 20590

96.4% in 2007 to 96.5% in 2008 in Washington’s 2008 statewide daytime survey.

Public Awareness Increases

Before and after each mobilization, the WTSC administered

public awareness surveys to licensed drivers at Washington

Department of Licensing offices across the State. Licensed

drivers who had read, seen, or heard any media about nighttime time seat belt enforcement increased significantly after

each intervention. Awareness, which started at 10% of all

survey respondents, peaked at 69% and finished the year at

49%. It was higher for 18- to 34-year-old males, a high-risk

group. Their awareness started at 12%, peaked at 78%, and

ended the first year at 55%.

Interestingly, when drivers see an officer stopped with motorist on the side of the road during the day, most reported that

they think that the stop is about speeding even during CIOT

campaigns. During nighttime hours, most think the stop is

about impaired driving.

Unbelted Nighttime Drivers Have Worse Driving 

And Criminal Records

The WTSC accessed driver abstracts (5 years) and criminal records (11 years) of drivers who were observed to be

unbuckled or who had received seat belt citations. In general,

unbelted drivers at night had the worst records when compared to daytime belted drivers. Tables 1 and 2 summarize

the results for the baseline period only before the beginning

of the program. They show driving record data (N = 1,926)

and criminal records (N = 1,715). Percentages for each group

(night unbelted and belted; day unbelted and belted)for drivers who had one or more of the violations or criminal acts on

theirrecords were divided by the day belted group’s percentage to create a ratio. Ratios greater than 1.0 had higher violation and criminal act rates than the daytime belted group.

Night unbelted drivers are 2.7 times more likely than day

belted drivers to have felony arrests on their criminalrecords,

3.0 times more likely to have alcohol citations, and 2.4 times

more likely to have license-related citations on their driving records.

Based on the first year’s activities, the nighttime seat belt

enforcement program in Washington is successful in raising

nighttime belt use rates without losing high daytime rates,

and in using paid and earned media to support nighttime

enforcement. Analysis of the second year of the program will

expand these results.

How to Order

To order Evaluation of the First Year of the Washington Nighttime Seat Belt Enforcement Program (82 pages plus appendices), prepared by Dunlap and Associates, write to the Office

of Behavioral Safety Research, NHTSA, NTI-130, 1200 New

Jersey Avenue SE., Washington, DC 20590, fax 202-366-7394,

or download from www.nhtsa.gov. John Siegler, Ph.D.,

was the Contracting Officer’s Technical Representative for

this project.

Table 1. One or more driving violations by belt use and time of day: Baseline period April 26 to May 1, 2007

Driver Group

Alcohol Citations Any Moving Violation Speeding Citations

Negligent or Reckless 

Citations

License-Related 

Citations

% of Group Ratio* % of Group Ratio* % of Group Ratio* % of Group Ratio* % of Group Ratio*

Night** Unbelted 10.4 3.0 55.4 1.4 42.1 1.3 10.4 2.1 14.6 2.4

Night Belted 4.9 1.4 49.0 1.3 35.6 1.1 8.4 1.7 11.0 1.8

Day*** Unbelted 5.7 1.6 45.1 1.1 33.2 1.0 7.3 1.5 7.8 1.3

Day Belted 3.5 1.0 39.2 1.0 32.3 1.0 4.9 1.0 6.0 1.0

Table 2. One or more criminal offenses by belt use and time of day: Baseline period April 26 to May 1, 2007

Driver Group

Any Criminal Offense Felonies Violent Crimes

% of Group Ratio* % of Group Ratio* % of Group Ratio*

Night** Unbelted 19.8 2.1 8.3 2.7 9.1 2.2

Night Belted 13.6 1.4 6.9 2.2 6.9 1.7

Day*** Unbelted 9.4 1.0 3.2 1.0 3.5 0.9

Day Belted 9.6 1.0 3.1 1.0 4.1 1.0

*Ratio is the quotient of the percentage in each category divided by the percentage of day belted drivers. **6 p.m. to 5:59 a.m. ***6 a.m. to 5:59 p.m.