Traffic Safety Facts

Traffic Tech – Technology Transfer Series

U.S. Department of Transportation 1200 New Jersey Avenue SE., Washington, DC 20590

National Highway Traffic Safety Administration

Number 385 April 2010

Seat Belt Use Increases in Maine Following 

Change to Primary Enforcement

Primary seat belt laws are associated with higher selfreported seat belt use rates and fewer traffic fatalities following enactment. Primary laws allow police to issue a citation 

solely upon observation of a seat belt violation. In contrast, 

secondary laws require that police first observe another violation (e.g., speeding) before being able to issue a seat belt 

citation. States with primary laws have higher observed seat 

belt usage rates than those with secondary laws. As of July 

2008, 26 States had primary belt laws.

Maine upgraded its seat belt law from secondary to primary, 

effective September 20, 2007, with an educational grace period 

to April 1, 2008. Preusser Research Group examined the effect 

of the law change on public awareness of the new law, seat 

belt use, and police attitudes. They collected data both before 

and after enforcement of the law and immediately following 

Maine’s Click It or Ticket May 2008 mobilization.

Method

This evaluation consisted of three parts: (1) public awareness surveys, (2) seat belt observations, and (3) police focus 

groups. Researchers assessed public awareness of the new 

law and observed seat belt use in three waves. Wave 1 took 

place in late February 2008, when the primary law upgrade 

had already gone into effect but police could only issue 

warnings (unless another violation also occurred). Wave 2 

took place in late April/early May when law enforcement 

was allowed to fully enforce seat belt violations under the 

primary law rules. Between Wave 1 and Wave 2, Maine conducted a media campaign to raise public awareness of the 

primary belt law, and many police departments conducted 

high-visibility enforcement campaigns during this time. 

Wave 3 took place after May 30, following the nationwide 

Click It or Ticket mobilization. 

Results

Public Awareness

Public awareness surveys showed that Maine drivers were 

aware of the law change and were cognizant of its consequences. As shown in Figure 1 below, the percentage of 

respondents who believed that Police can give you a seat belt 

ticket whenever they see you not wearing your seat belt increased 

from Wave 1 (pre-enforcement) to Wave 2 (post-enforcement).

Figure 1. Knowledge of the Seat Belt Law

72%

74%

76%

78%

80%

82%

84%

86%

88%

Wave 1 Wave 2 Wave 3

Police can give you a seat belt ticket 

whenever they see you not wearing your seat belt

87% 87%

78%

Motorists also felt there was an increase in strictness of 

enforcement. Survey results showed that motorists’ perceptions of enforcement certainty, both at the local and State levels, increased significantly. 

The percentage of respondents who reported having seen or 

heard about increased enforcement or messages encouraging 

the use of seat belts also increased over time (see Figure 2). 

There was also a clearly marked increase in the percentage 

of respondents recognizing the slogan Click It or Ticket, going 

from 38% in Wave 1 to 46% in Wave 2, reaching a high of 64% 

after the May mobilization.
Figure 2. Awareness of Messages

0%

10%

20%

30%

40%

50%

60%

70%

80%

90%

Enforcement Belt Message

Wave 1 Wave 2 Wave 3

Have you recently seen or heard about (% yes)

27%

48%

66%

53%

71%

77%

Observed Seat Belt Use

Field observers made approximately 27,000 belt use observations as part of this evaluation: 23,000 during the day and 

4,000 at night. Observed seat belt use increased from each 

wave to the next during both day and night (see Figure 3). 

Figure 3. Observed Seat Belt Use by Day and Night

Night Day

Percent Belted

2 3

Wave

1

50.0

55.0

60.0

65.0

70.0

75.0

80.0

85.0

90.0

69.3

76.9 76.9

79.2

81.2

83.8

Across the three waves, daytime seat belt use increased from 

77% to 84%, and nighttime belt use rose from 69% to 81%. 

Although daytime belt use was higher than nighttime use in 

general, the impact of the law change was greater for night 

belt use than for day belt use. Almost all demographic groups 

showed increases in belt use across waves (see Figure 4).

Police Focus Groups

Focus groups with law enforcement showed that officers 

responded positively to the change in law. All agencies 

believed that the level of seat belt enforcement activity on 

regular patrols increased during the six-month transition 

when warnings were permitted on primary seat belt stops 

and after April 2008 when standard enforcement went into 

effect. They generally believed that motorists were buckling 

up more frequently following the law change and have had 

no negative feedback about primary enforcement. 

Figure 4. Observed Seat Belt Use by Vehicle Type

Wave 1 Wave 2 Wave 3

Daytime Car

Daytime SUV

Daytime Pickup

Daytime Van

Nighttime Car

Nighttime SUV Nighttime Van

Nighttime Pickup

50%

60%

70%

80%

90%

100%

Summary

Maine drivers were aware of the law change and adjusted 

their behavior accordingly. Belt use increased during daylight hours and increased even more at night when crash 

risk per mile driven is at its highest. These results should be 

of particular interest to those States that still have secondary 

belt use enforcement laws and are considering upgrading to 

primary laws.

How to Order

To order Evaluation of Maine’s Seat Belt Law Change 

From Secondary to Primary Enforcement (25 pages 

plus appendices), write to the Office of Behavioral Safety 

Research, NHTSA, NTI-132, 1200 New Jersey Avenue SE., 

Washington, DC 20590, fax 202-366-7394, or download from 

www.nhtsa.dot.gov.

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 Dr. Angela 

Eichelberger, Editor, by sending a fax to 202-366-7394, or e-mail 

angela.eichelberger@dot.gov. 

1200 New Jersey Avenue SE., NTI-130

Washington, DC 20590