The findings being released Thursday are based on 11,000 interviews with people of driving age from 2009 to 2012 conducted on behalf of the AAA Foundation for Traffic Safety. Some of the drivers may have been interviewed more than once over the four years, AAA said.
"Motorists may be growing more complacent about potential safety risks behind the wheel," said Peter Kissinger, the foundation's president and CEO. "A 'do as I say, not as I do' attitude remains common with many motorists consistently admitting to engaging in the same dangerous behaviors for which they would condemn other drivers.
There were more than 34,000 traffic deaths in 2012, a 5.3 percent increase. That was the first annual increase in seven years, according to the National Highway Traffic Safety Administration. More than 2.3 million people annually also suffer serious injuries from crashes.
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The share of people who said they believe driving after drinking is a very serious threat declined from an overwhelming 90 percent in 2009 to 69 percent in 2012. The share of people who said they consider driving after drinking "completely unacceptable" also declined, but less dramatically - from 95 percent in 2009 to 89 percent last year. Fourteen percent of those surveyed acknowledged driving when they thought their blood alcohol levels were close to or possibly over the legal limit last year.
Driving when so drowsy that it's difficult for a driver to keep his or her eyes opened was viewed as a serious threat by 46 percent of those surveyed last year, down from 71 percent in 2009.
The share of people who said they consider running a red light when a driver had time to stop to be completely unacceptable also declined, from 77 percent in 2009 to 70 percent in 2012. More than a third—8 percent—admitted to running a red light within the previous month.
About three-quarters of those surveyed said it's unacceptable to drive 15 mph or more over the speed limit on residential streets, but far fewer—from 39 percent to 46 percent over the four years—considered it unacceptable to speed on freeways.
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Part of the problem may be that public and media attention to highway safety has been waning, said Jonathan Adkins, a spokesman for the Governors Highway Safety Association, which represents state highway safety offices.
Four years ago, then-Transportation Secretary Ray LaHood launched a federal campaign against distracted driving, attracting massive attention to the issue of texting and talking on the phone behind the wheel. About the same time, claims of Toyota cars with stuck accelerators were prominent in the news and the focus of congressional hearings.
"Much of that has died down," Adkins said. "Also, when highway fatalities go down, as they have until just very recently, there is less attention paid to it by the media and people tend to feel like that problem has been solved. Highway safety in general has always been difficult to make a big concern among the public despite the high numbers (of deaths)."