A national study shows a 5 mph speed limit increase resulted in an 8% bump in car accident fatalities — causing 33,000 preventable auto accident deaths over 18 years
As if it were necessary, here is yet more proof that speed limit increases — like the ones just passed by the Michigan Legislature and signed by Gov. Rick Snyder in 2016 — lead to increased car accident wrongful death fatalities.
In its study, “Relationship of Traffic Fatality Rates to Maximum State Speed Limits,” the Insurance Institute for Highway Safety (IIHS) determined that:
- “A 5 mph increase in the maximum state speed limit was associated with an 8% increase in fatality rates on interstates and freeways and a 4% increase on other roads.”
- “In total, there were an estimated 33,000 more traffic fatalities during the years 1995-2013 than would have been expected if maximum speed limits had not increased. In 2013 alone, there were approximately 1,900 additional deaths — 500 on interstates/freeways and 1,400 on other roads.”
Additionally, the IIHS’s study noted there was not only “a definite trend of increased fatality risk when speed limits are raised,” but the “increase in risk has been so great that it has now largely offset the beneficial effects of some other traffic safety strategies,” such as frontal airbags.
The IIHS’s study results confirm what I’ve been saying for years: Speed kills!
As a Michigan auto accident lawyer, I have been outspoken against raising the speed limits in this state. In my blog post criticizing the speed limit increases that were approved in Michigan in early 2017, I pointed out the research showing that driving at faster speeds will cause more people to die:
- Raising the speed limit from 70 mph to 75 mph on freeways is estimated to increase motor vehicle accident-related fatalities by 17% (according to an MDOT-sponsored study).
- Raising the speed limit from 55 mph to 65 mph on non-freeways, i.e., highways, is estimated to increase in car accident traffic fatalities by 28% (according to an MDOT-sponsored study).
- Fatalities increased 19.2% and serious injuries increased 39.8% when Michigan raised its speed limit on rural limited access highways from 55 mph to 65 mph in December 1987 (according to a 1990 study by the University of Michigan Transportation Research Institute).
The faster speed limits that will drive up Michigan car accident fatalities
As a result of House Bills 4423 and 4425 (Public Acts 445 and 447 of 2016), which were signed into law on January 5, 2017, the speed limit for cars, trucks and school buses on Michigan freeways and highways will increase as follows:
- Freeway maximum speed limit will increase from 70 mph to 75 mph.
- Highway maximum speed limit will increase from 55 mph to 65 mph.
- Trucks’ maximum highway and freeway speed limit will increase from 55 mph/60 mph to 65 mph.
- School buses’ maximum highway and freeway speed limit will increase from 55 mph/60 mph to 65 mph.
