SPECIAL REPORT: Split data at the heart of battle over split speed limits

| 6/13/2003

The AAA Chicago Motor Club wants speed limits split in Illinois, and the group says it has statistics to back it up.

But on the other side of the fence, OOIDA, a former federal official and numerous studies say statistics support an end to splits.

At the heart of the battle over split speed limits in Illinois is a fight over figures. And as HB1186, a bill that would end slower speeds for trucks, awaits the decision of Gov. Rod Blagojevich, Land Line took a look at the number for both sides, and found some interesting conflicts.

Julie Cirillo, former assistant administrator and chief safety officer for the Federal Motor Carrier Safety Administration, recently testified in Ohio in favor of ending split speeds in that state.

“Vehicles traveling 10 to 15 mph slower than the mean speed of traffic were much more likely to be involved in accidents than vehicles traveling slightly above the mean speed,” the former federal official said.

“In 1963, David Solomon reported that deviation from the mean speed of traffic in both the negative and positive direction contributed significantly to the occurrence of accidents,” Cirillo said.

However, a spokeswoman for AAA says the group considers two other studies, conducted by the National Highway Traffic Safety Administration and Illinois DOT, to be more pertinent to the split speed issue.

“We think that those statistics hold up more because it’s been shown that there’s an increase with higher speeds, and that report was published this month,” Nicole Niemi, a public relations specialist with AAA Chicago, said.

According to Niemi, the June 2003 NHTSA study said 22 percent of accidents involving trucks were attributed to excessive speed. When asked how the study defined “excessive speed,” Niemi said an 80,000-pound truck takes 190 more feet to stop at 65 mph than if it were traveling at 55 mph.

Land Line discovered the NHTSA study says something entirely different.

The NHTSA study did say “a speed limit of 55 mph or higher, poor weather and a curved road significantly increase the odds of both a rollover and a jackknife for large trucks.” But it did not say 22 percent of large truck wrecks were caused by truck speeding. Neither did it use the phrase “excessive speeding.”

According to NHTSA, in accidents that involved a truck and another vehicle where law enforcement said speeding was a factor, officers said the truck was speeding in 22 percent of cases.

But speeding by the other vehicle, rather than the truck, was a factor in 78 percent of the accidents listed.

The NHTSA study also noted a similar pattern in other truck-car wreck statistics.

“There were 1,696 fatalities in head-on crashes involving a large combination truck and a passenger vehicle where the passenger vehicle was in the combination truck’s lane,” the study said. “There were only 177 fatalities in head-on crashes involving a large combination truck and a passenger vehicle where the combination truck was in the passenger vehicle’s lane.”

Figures from one of AAA’s own studies show a similar pattern. The AAA Foundation for Traffic Safety said one of its studies showed that when car-truck accidents occur, the car driver is at fault most of the time.

“Car drivers were found to make more errors than truckdrivers,” J. Scott Osberg, director of research, AAA Foundation for Traffic Safety, recently told Land Line. “The focus should be on the unsafe driving acts that lead to these fatal crashes.”

The foundation used federal statistics from the Department of Transportation’s Fatality Analysis Reporting System, the same source as the NHTSA study, to produce its April 2002 report on car-truck crashes, often cited by federal transportation officials.

The report, titled “Identifying Unsafe Driver Actions that Lead to Fatal Car-Truck Crashes,” said, “The results corroborate earlier studies of car-truck crashes showing that there are many more unsafe actions by car drivers than truckdrivers.”

Editor’s note: Jim Johnston, president of the Owner-Operator Independent Drivers Association recently wrote to Gov. Blagojevich of Illinois to express the association’s position on HB1186. To read Johnston’s letter, click here.

--by Mark H. Reddig, associate editor

Keith Goble and Dick Larsen of Land Line contributed to this report.

Mark Reddig can be reached at mark_reddig@landlinemag.com.