Fewer people die in motor vehicle crashes when drivers can be ticketed for seat belt violations even if they haven’t broken other laws, a U.S. study finds.
Researchers analyzed fatalities from 2001 to 2010 and found states with so-called primary seat belt laws - which allow traffic stops just for failure to wear seat belts - had death rates 17 percent lower than states with so-called secondary seat belt laws, which permit tickets only in conjunction with other violations.
“If a person thinks they are unlikely to be ticketed for any reason when in a car, then they also think odds they would get cited for not wearing a seat belt would be extremely low,” said lead researcher Dr. Lois Lee from Boston Children’s Hospital.
Lee and colleagues identified 283,183 crash fatalities among vehicle occupants age 10 and older over the course of the study period. Younger passengers were excluded because they might have been using child safety seats or booster seats instead of seat belts.
In 2001, on average, out of every 100,000 people, 14.6 died in a motor vehicle accident, the study found. That year, 16 states had primary seat belt laws and 33 had secondary seat belt laws.
By 2010, 30 states had primary seat belt laws and the average fatality rate dropped to 9.7 people per 100,000.
That year, states with primary and secondary laws didn’t differ significantly in the percentages of vehicles older than five years old involved in crashes, speeding-related accidents, crashes due to bad weather or drunk driving collisions.
But the percentage of crashes in which no restraint was used was significantly lower in states with primary laws than in those with secondary laws.
At the same time, some people who are more prone to skip buckling up – such as men, drivers under 24, and residents of rural areas – had higher self-reported seat belt use in states with primary laws.
“The take home message is, regardless of what type of law your state has, you and all your passengers should wear a seat belt every time with every ride in the car since seat belts are the most effective means of decreasing injury and death in the event of a car crash,” Lee said by email.
One limitation of the study is that it lacked data on deaths that occurred more than a month after the crash, the researchers acknowledge in Annals of Internal Medicine. It also didn’t assess injury prevention linked to seat belts and had no data on how aggressively the seat belt laws were enforced.
“Seat belt use is a proven method to reduce motor vehicle occupant injuries,” said Grant Baldwin, an injury prevention researcher at the U.S. Centers for Disease Control and Prevention who co-authored an editorial accompanying the study.
More traffic stops, and steeper fines and penalties for tickets can both help encourage seat belt use, Grant said by email. Previous research has also shown that seat belt use increased by approximately 10 percentage points when states changed from secondary to primary seat belt laws, he said.
In past surveys, people who rarely or never use seat belts or child safety seats have said they would use the devices if it was required by law, noted Raymond Bingham, a professor at the University of Michigan's Transportation Research Institute in Ann Arbor who wasn't involved in the study.
“People give all sorts of reasons for not wearing their seat belts,” he said. “Some say they’re uncomfortable, some believe myths that seat belts cause more serious injuries, others just don’t want to be told what to do by the government.”
Often, the threat of a ticket is enough to get many people to buckle up, as long as fines are steep enough that people want to avoid them, Bingham said by email.
“What we have seen for years is that when secondary laws are passed in states that do not require seat belt use, usage rates go up considerably,” he said. “Another sizable jump is seen when states transition from secondary to primary enforcement. This is most likely attributable to people not waiting to get a ticket and feeling like their chances are much less, which they are, when a secondary law is in place.”
Researchers analyzed fatalities from 2001 to 2010 and found states with so-called primary seat belt laws - which allow traffic stops just for failure to wear seat belts - had death rates 17 percent lower than states with so-called secondary seat belt laws, which permit tickets only in conjunction with other violations.
“If a person thinks they are unlikely to be ticketed for any reason when in a car, then they also think odds they would get cited for not wearing a seat belt would be extremely low,” said lead researcher Dr. Lois Lee from Boston Children’s Hospital.
Lee and colleagues identified 283,183 crash fatalities among vehicle occupants age 10 and older over the course of the study period. Younger passengers were excluded because they might have been using child safety seats or booster seats instead of seat belts.
In 2001, on average, out of every 100,000 people, 14.6 died in a motor vehicle accident, the study found. That year, 16 states had primary seat belt laws and 33 had secondary seat belt laws.
By 2010, 30 states had primary seat belt laws and the average fatality rate dropped to 9.7 people per 100,000.
That year, states with primary and secondary laws didn’t differ significantly in the percentages of vehicles older than five years old involved in crashes, speeding-related accidents, crashes due to bad weather or drunk driving collisions.
But the percentage of crashes in which no restraint was used was significantly lower in states with primary laws than in those with secondary laws.
At the same time, some people who are more prone to skip buckling up – such as men, drivers under 24, and residents of rural areas – had higher self-reported seat belt use in states with primary laws.
“The take home message is, regardless of what type of law your state has, you and all your passengers should wear a seat belt every time with every ride in the car since seat belts are the most effective means of decreasing injury and death in the event of a car crash,” Lee said by email.
One limitation of the study is that it lacked data on deaths that occurred more than a month after the crash, the researchers acknowledge in Annals of Internal Medicine. It also didn’t assess injury prevention linked to seat belts and had no data on how aggressively the seat belt laws were enforced.
“Seat belt use is a proven method to reduce motor vehicle occupant injuries,” said Grant Baldwin, an injury prevention researcher at the U.S. Centers for Disease Control and Prevention who co-authored an editorial accompanying the study.
More traffic stops, and steeper fines and penalties for tickets can both help encourage seat belt use, Grant said by email. Previous research has also shown that seat belt use increased by approximately 10 percentage points when states changed from secondary to primary seat belt laws, he said.
In past surveys, people who rarely or never use seat belts or child safety seats have said they would use the devices if it was required by law, noted Raymond Bingham, a professor at the University of Michigan's Transportation Research Institute in Ann Arbor who wasn't involved in the study.
“People give all sorts of reasons for not wearing their seat belts,” he said. “Some say they’re uncomfortable, some believe myths that seat belts cause more serious injuries, others just don’t want to be told what to do by the government.”
Often, the threat of a ticket is enough to get many people to buckle up, as long as fines are steep enough that people want to avoid them, Bingham said by email.
“What we have seen for years is that when secondary laws are passed in states that do not require seat belt use, usage rates go up considerably,” he said. “Another sizable jump is seen when states transition from secondary to primary enforcement. This is most likely attributable to people not waiting to get a ticket and feeling like their chances are much less, which they are, when a secondary law is in place.”
