It remains the conventional wisdom that sitting in the back of a vehicle is safer than sitting in the front, especially for passengers in the "death seat," as the spot next to the driver used to be called.
But that thinking is out of date. Major advances in car safety -- from basic air bags and "crumple zones" to seat belts that absorb the force of impacts during a crash -- have greatly reduced the likelihood of getting injured or killed while riding in the front seat. But far less progress has been made protecting backseat passengers.
"We don't have crash dummies in the rear. So things are improving in the front, but the backseat hasn't kept up," said Jessica Jermakian, a senior research scientist at the Insurance Institute for Highway Safety, or IIHS. "For adult occupants, we wouldn't necessarily say it's safer [in the rear] anymore."
The issue of safety for car passengers surfaced again this week after veteran newsman and "60 Minutes" correspondent Bob Simon was killed in a crash while riding in a livery cab in Manhattan.
Simon, 73, was not wearing a seat belt at the time of the Wednesday night crash. Although there is no way to know whether a seat belt would have saved his life, the accident underscores the safety concerns related to car accidents, especially for those riding in the back.
The chances of surviving any serious car crash vary widely, depending on the nature of the collision, speed and type of vehicles involved. But for people seated in the front, those odds have improved significantly over the last two decades as regulators started requiring automakers to install air bags. Understandably, the car industry's focus has been on better protecting riders in the front because that's where most passengers, or roughly 88 percent, sit.
"Historically, the rear seat has been safer," Jermakian said. "In older vehicles without all these restraint improvements, being in the front seat put you closer to the crash, and you don't have all those hard points in the back."
For children, the back remains the safest place to ride. Children 12 and younger account for 56 percent of passengers who sit in the back of vehicles, but only 24 percent of crash fatalities, according to a recent study by the IIHS and the Children's Hospital of Philadelphia that reviewed U.S. accidents between 2007 and 2012.
The same is not true for adults. For those 55 and older, even those using seat belts were more likely to die in a crash while seated in the back than in the front, according to the study. Researchers said that was consistent with prior data showing that adults in the rear are more likely than adults in the front to sustain chest injuries. They also said there was "some evidence of an elevated risk of head and neck injuries for restrained women seated in the rear compared with the front."
Other factors could help explain why rear-seat passengers are at risk. For one, many people who make a point of buckling up in the front, often because it is the law, are less likely to use seat belts when riding in the back. That may partly come down to comfort, said Joan Claybrook, president of Public Citizen from 1982 to 2009.
"The belts should be better designed so people would be more likely to use them," she said, noting that many cars are made to hold three people in the back, making the belts clumsier to use and less comfortable.
And while cars commonly use a repeating tone to remind people in the front to fasten their seat belts, no such mechanism is activated if backseat passengers opt not to buckle up, Claybrook pointed out.
Adult rear-row occupants were less likely to use seat belts, with just 70 percent of those ages 20 to 54, and 86 percent of those 55 and older using restraints, according to the study. That compares with 99 percent for infants, 96 percent for those 4 to 8 and 93 percent for 9 to 12.
Seat belts are an important factor in preventing passengers from being thrown from the vehicle in a crash, one of the deadliest outcomes.
"In fatal crashes in 2012, 79 percent of passenger vehicle occupants who were totally ejected from the vehicles were killed," a spokesperson for the National Highway Traffic Safety Administration said. "Only one percent of the occupants reported to have been using restraints were totally ejected, compared with 30 percent of the unrestrained occupants."
If car makers have done less to enhance the safety of rear-seat passengers, they are investing big bucks in technology aimed at avoiding accidents altogether, including lane detection warning systems and automatic brakes.
"A lot of the technologies are moving away from crash worthiness to crash avoidance -- that's the shift we see taking place across the entire industry," said Jeremy Carslon, senior analyst within the automotive technology unit at IHS, a supplier of business analytics. "There's not a terrible amount of activity, relatively speaking, in the backseat as opposed to the front."
Yet the study released by IIHS and Children's Hospital of Philadelphia found rear-seat occupants could benefit from some of the same technologies used to protect drivers and front passengers.
"Front air bags, side air bags and knee air bags, plus features that ready safety belts when a crash is imminent and limit the amount of energy that is transferred to an occupant, are among those innovations," said a statement accompanying the Insurance Institute study, which analyzed real-world data on crashes.
"We spent a lot of time for good reason looking at the front seat. Now there is some movement towards looking at what we can do for the rear," Jermakian said.