By Michael Brenneis
As a vehicle’s speed increases, it’s kinetic energy increases exponentially. Should a vehicle crash, its kinetic energy is transferred, often catastrophically, into the structure of the vehicle, its occupants, other vehicles, the surrounding built environment, or nearby pedestrians or cyclists. A small amount of speed reduction can translate into a big reduction of kinetic energy, and reduces the potential severity of a crash. Higher speed and speeding also increases stopping distance, and compresses the amount of time drivers have to react.
A new report from the Governors Highway Safety Association (GHSA) takes a comprehensive look at speeding on American roadways, including observations about who is speeding, why they are speeding, and what can be done to reduce it.
In 2017 speeding-related fatalities accounted for about 26 percent of the total number of traffic fatalities. Yet speeding mitigation receives less attention and less funding than other deadly behaviors such as impaired driving or lack of seat-belt use.
The desire to reduce travel time and motorist delay has contributed to a historical prioritization of the movement of cars at high speed. The design of our roadways with this goal in mind has had the unintended consequence of making many drivers feel comfortable exceeding the speed limit. Speeding is a significant safety problem as media coverage from Houston makes clear. Many advocates conclude that safer conditions for all road users should now be prioritized over motorist speed.
From the GHSA report:
A 2017 national survey of drivers conducted by (AAA Foundation for Traffic Safety) found that half of motorists (50.3%) reported exceeding the speed limit by 15 mph on a freeway and 47.6% reported driving 10 mph over the speed limit on a residential street in the past month. In addition, this study found that there is a greater disapproval by drivers for speeding on a residential street than on freeways. Of those respondents, 79.3% feel that speeding on freeways is a serious or somewhat serious threat to their safety, and 88.2% view drivers speeding on residential streets as a very serious or somewhat serious threat to their personal safety. However, 23.9% of respondents believed that speeding 15 mph above the posted speed limit on the freeway is “completely” or “somewhat” acceptable.
A lot of people recognize that speeding is a problem, but they do it anyway. It’s not always that they’re conscious scofflaws; they may be lulled into a speeding complacency. Driving roads that are designed to encourage unsafe speeds, they grow accustomed to driving fast. And observing other drivers speeding with little consequence leads to an assumption that the risk is minimal. Some states are increasing speed limits even though higher limits have been shown to reduce safety and increase speeding.
The numbers may also be under-reported. Crash reports will sometimes report speeding as “driving too fast for conditions.” GHSA recommends standardizing crash data collection.
Speeding mitigation has historically fallen into either an enforcement or public outreach category. Automated enforcement, increasingly shown to be an effective deterrent, faces political and popular opposition. Other technological solutions such as speed governors, or in-vehicle speed alert systems linked to GPS and high-quality speed limit maps, could be implemented or developed in connected vehicles. The GHSA also supports shifting the culture away from accepting speeding to viewing drivers who speed as wrong-doers and developing a voice for the victims of crashes due to speeding, in the same way that drunk-driver victims were previously elevated.
Michael Brenneis is an Associate Researcher at SSTI.