Number 400 November 2010

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

National Highway Traffic Safety Administration

Increasing seat belt usage in the United States has proved to be a

slow and difficult task. It has taken about 30 years since NHTSA

conducted the first seat belt and child restraint workshops in

1978 to reach 84% usage in 2009. In general, seat belt laws and

their enforcement have received the greatest emphasis since

1984. There has been less emphasis on increasing fine amounts

as a means to increase usage, in spite of positive circumstantial

and research evidence.

Bedford Research and the Pacific Institute for Research and

Evaluation conducted a study for NHTSA to determine the relative impact of primary seat belt laws and fine amounts on seat

belt usage. This research examined changes in usage associated

with past activities and estimated gains that might be expected

in the future.

Analytic Method

This study determined the impact of various predictors on

two measures of seat belt use, using panel regression

analyses. The first measure was the percentage of buckled

front-seat occupants over age 8 killed in passenger vehicles, as

found in NHTSA’s Fatality Analysis Reporting System (FARS),

which is a census of all crashes involving fatalities in the

United States. Because seat belt use among the fatally injured

is consistently measured, FARS use is a reliable estimate of

belt use. The second measure was the percentage of front-seat

occupants of passenger vehicles observed to be buckled up in

annual statewide observational surveys conducted by each

State in accordance with criteria established by NHTSA.

Penalties (Fines Plus Fees) for Seat Belt Violations

Based on information obtained from the States, penalty

amounts (fines plus fees and court costs) have increased over

the past decade. The sum of these charges averaged $35 in 2000

and $49 in 2008. Twenty-six States increased their total penalty

by at least $5. In these 26 States, the average penalty increased

from $39 to $70. FARS use increased by an average of about 9.1

percentage points. In the remaining 24 States, there was a small

decline (on average) in total fine-and-fee amount, from $30 in

2000 to $26 in 2008. FARS use increased by 6 points in these 24

States, about two-thirds the gain experienced by the 26 States

that increased their total fine plus fee assessments.

High-Belt-Use States Versus Low-Belt-Use States

States were ranked by their two most recent years of observed

seat belt use (2007-2008) and placed into three groups based

on these rankings. They were: “Top 10,” “Bottom 10,” and a

“Middle” group of 30 States plus the District of Columbia. Nine

of the 10 States with the highest use had primary seatbelt laws;

nearly half of the middle group had such laws; and only 3 of the

10 States with the lowest use had primary laws. New Hampshire,

among the 10 States with the lowest use, has no adult seat belt law.

Table 1 shows that the top 10 States had the highest fines, highest overall penalties (fines and fees), and the highest per capita

Click It or Ticket (CIOT) citation rates, compared with the middle

and bottom groups. States with the lowest seat belt use rates had

the highest per capita expenditures for paid media during May

CIOT mobilizations.

Table 1. High-, Middle-, and Low-Seat-Belt-Use States*

Top 10

States

(Average)

Middle 31

States

(Average)

Bottom 10 

States

(Average)

Observed Belt Use 

(2007-08) 94.0% 84.0% 71.7%

FARS Belt Use 

(2006-07) 59.2% 45.2% 33.5%

Fines Only 

(2003-08) $52.63 $23.58 $24.67

Fines + Fees 

(2008) $81.62 $43.79 $26.28

Citations, per 10K pop. 

(2003-08)** 23.0 21.7 13.4

Media $, per capita 

(2003-08)** $0.07 $0.08 $0.09

* States were grouped on the basis of observed statewide seat belt use 

rates in 2007 and 2008.

** During the national Click It or Ticket seat belt campaign.

Impact of Law Type, Fines, Enforcement, and Media

There were two time periods examined in this study: 1997-2002,

a period of Operation Always Buckle Children (ABC) mobilizations,

and 2003-2008, a period of CIOT mobilizations.

Primary seat belt laws(versus secondary laws) had the most consistent impact on seat belt usage across the two time periods. Table 2

shows that primary laws accounted for 10- to 12-percentage-point

increases in seat belt usage among occupants observed during

daytime hours (observed use) and 9-point increases among occupants killed in crashes (FARS use).

Primary Laws and Fine Levels Are Associated 

With Increases in Seat Belt Use, 1997–2008

TRAFFIC TECH

Technology Transfer Series
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, fax 202-366-7394, e-mail: angela.eichelberger@dot.gov.

1200 New Jersey Avenue SE., NTI-130

Washington, DC 20590

Higher fines were associated with higher seat belt use, particularly in the most recent time period (2003-2008). The results

showed that increasing the fine amount from $5 to $25 had

approximately the same effect as changing the fine from $25 to

$60; both were associated with 3- to 4-point increases in usage

in primary or secondary law States. A fine increase of $60 to

$100 was associated with gains of 2 to 3 percentage points in belt

use. Little improvement was associated with fines above $100,

but there were few States with fines above this level.

Table 2. Percentage-Point Increases in Seat Belt 

Use Associated With Laws and Fine Amounts

Percentage Point Increase in Seat Belt Use

1997 – 2002 Period 2003 – 2008 Period

FARS Observed FARS Observed

Law Upgrade

Primary vs. 

Secondary +9.1 +11.9 +9.0 +10.4

Fine Increase

$5 to $100 +9.4 +8.7 +10.6 +10.8

$5 to $25 +3.3 +3.1 +3.8 +3.8

$25 to $60 +3.3 +3.1 +3.7 +3.8

$60 to $100 +2.7 +2.5 +3.1 +3.1

Enforcement, as reported during the two weeks of the mobilizations each year, was related to higher FARS and observed seat

belt use. These measures, however, were deemed too unreliable

to estimate potential gains in annual seat belt use because of

reporting limitations.

Media expenditures as reported during the two CIOT weeks

were not associated with increases in usage after accounting for variations associated with laws, fines, and enforcement. Some low-use States focused on media more than

actual enforcement.

Effect on the Odds of Seat Belt Use

The analysis also examined the change in the odds of seat belt

use associated with each predictor. The odds ratio is a measure

of the odds of being buckled up in any given year, divided by

the odds of being buckled in the baseline year. This measure

is more sensitive to relative change for States that already have

high use rates. Table 3 shows the percent increase in the odds of

seat belt use. Primary laws (versus secondary laws) were associated with 7.9 to 26.2 percent increases in the odds of belt use. A

fine increase from the median $25 to $100 was associated with

11.3 to 29.6 percent increases in belt use.

Table 3. Percent Increases in Odds of Seat Belt Use

Associated With Laws and Fine Amounts*

Percent Increase in Odds of Seat Belt Use

1997 – 2002 Period 2003 – 2008 Period

FARS Observed FARS** Observed

Law Upgrade

Primary vs. 

Secondary 17.9 26.2 7.9 20.0

Fine Increase

$5 to $100 35.7 25.1 22.5 59.1

$5 to $25 27.7 19.5 17.5 45.9

$25 to $60 17.9 12.6 11.3 29.6

$60 to $100 9.8 6.9 6.2 16.2

* Percentage change is relative to baseline: 1995–1996 for the Operation 

ABC period and 2000–2002 for the CIOT period.

** FARS use was based on 2003-2007 for the CIOT period.

Summary and Conclusions

These analyses confirmed that primary seat belt laws and

fine increases were associated with higher use rates and with

increases in the odds of being buckled.

1.	 Fine amounts were consistently associated with seat belt

use across the two time periods and for both FARS and

observed belt use. An increase in fine level from $25 (the

current median value in both primary and secondary law

States) to $60 was associated with a 3- to 4-percentage-point

increase in both FARS and observed seat belt use. Increasing a State’s fine level from $25 to $100 was associated with

a 6- to 7-point increase in both use rates.

2.	 An upgrade from secondary to primary enforcement was

associated with a 10- to 12-percentage-point increases

in observed use and 9-point increases in FARS use. This

increase is additive to the increase associated with a fine

increase.

In summary, increasing fine levels is a strategy that has potential to further raise seat belt use, in addition to primary law

upgrades and high-visibility enforcement. Although the regression analyses did not find a statistically significant effect associated with media, the public needs to be aware of laws and fine

changes before compliance is likely. Publicizing fine increases is

essential for maximizing their effectiveness.

How to Order

To order Strategies to Increase Seat Belt Use: An Analysis of 

Levels of Fines and the Type of Law (40 pages plus appendices),

write to the Office of Behavioral Safety Research, NHTSA, NTI130, 1200 New Jersey Avenue SE., Washington, DC 20590, fax

202-366-7394, or download from www.nhtsa.gov.