The study by Triple-A's Foundation for Traffic Safety finds that people age 85 and up are nearly four times more likely than middle-aged drivers to be killed if they get into a crash.
The study finds that as drivers age, they suffer increasingly from decreased perception and motor skills. Frailty also causes more serious injury and death in crashes.
The study also finds left turns are the major culprit, because they sometimes require quick judgments. However, the study also says that drivers in their late 50s and early 60s are among the safest on the roads.
The association says the study proves what's been suspected all along. It didn't recommend any new laws.