Skip to main content

US speed limit increases ‘cause 33,000 deaths in 20 years’

A new Insurance Institute for Highway Safety (IIHS) study, which looked at the impact of speed limit increases in 41 states over a 20-year period starting in 1993, shows that increases in speed limits over two decades have cost 33,000 lives in the US In 2013 alone. The increases resulted in 1,900 additional deaths, essentially cancelling out the number of lives saved by frontal airbags that year. "Although fatality rates fell during the study period, they would have been much lower if not for states' dec
April 14, 2016 Read time: 2 mins
A new Insurance Institute for Highway Safety (IIHS) study, which looked at the impact of speed limit increases in 41 states over a 20-year period starting in 1993, shows that increases in speed limits over two decades have cost 33,000 lives in the US. In 2013 alone, the increases resulted in 1,900 additional deaths, essentially cancelling out the number of lives saved by frontal airbags that year.

"Although fatality rates fell during the study period, they would have been much lower if not for states' decisions to raise speed limits," says Charles Farmer, IIHS vice president for research and statistical services and the author of the study.

Farmer looked at deaths per billion miles travelled by state and roadway type. He then considered factors like alcohol consumption, changes in unemployment and the number of young drivers aged 16-24, all of which could affect the fatality rate. Overall, he found that the number of deaths climbed 4 percent with each 5 mph increase in the maximum speed limit.

Maximum speed limits are set by the states and they have been rising since 1995. However, during most of the 1970s and 1980s, the threat of financial penalties held state speed limits to 55 mph.

Today, six states have 80 mph limits, and drivers in Texas can legally drive at 85 mph on some roads.

As large a number as it is, 33,000 is likely an underestimate, Farmer says, as he only considered increases in the maximum speed limit, which often applies only to rural interstates, but many states also increased speed limits on urban interstates. Other states increased speed limits on one section of road and later extended the higher limit to other sections. Those subsequent changes weren't factored in.

"Since 2013, speeds have only become more extreme, and the trend shows no sign of abating," Farmer notes. "We hope state lawmakers will keep in mind the deadly consequences of higher speeds when they consider raising limits."

Related Content

  • November 3, 2015
    New hands-free technologies pose hidden dangers for drivers
    Potentially unsafe mental distractions can persist for as long as 27 seconds after dialling, changing music or sending a text using voice commands, according to surprising new research by the AAA Foundation for Traffic Safety. The results raise new and unexpected concerns regarding the use of phones and vehicle information systems while driving. This research represents the third phase of the Foundation’s comprehensive investigation into cognitive distraction, which shows that new hands-free technologies ca
  • April 22, 2016
    ATS study claims distracted red-light running is on the rise
    Analysis released during National Distracted Driving Awareness Month by American Traffic Solutions (ATS), Distracted on Red, showcases the dangers of distracted driving behaviour and impact on red-light running. ATS sampled data from 67 intersections with red-light safety cameras across the United States over a three-month period. Distractions were coded into several categories, including cell phone use, looking away, eyes closed, smoking, eating/drinking, reading and applying make-up. ATS data showed distr
  • March 14, 2014
    Rear-view cameras ‘more effective than parking sensors’
    Rear cameras are more effective than parking sensors at helping drivers avoid objects while travelling in reverse, but they don't help in every situation, a new Insurance Institute for Highway Safety (IIHS) study shows. The study, conducted with volunteer drivers in an empty parking lot in the Los Angeles area, indicates that cameras would help prevent more reversing crashes into pedestrians in the vehicle's blind zone than parking sensors. Surprisingly, cameras by themselves worked better than sensors a
  • November 21, 2014
    Ho Chi Minh City ‘must invest in transportation system’
    Ho Chi Minh City (HCMC) could generate economic benefits of US$1.4 billion by investing in making its transportation system more resilient in extreme weather conditions, a study released by Siemens and consulting firm Arup today shows. Siemens and the Arup prepared the study, to show how intelligent infrastructure can assist cities in addressing the increased demand and at the same time offer better protection of their transport networks against extreme weather events. Calculations based on a review o