The number of fatal motorcycle accidents rose in 2007 for the 10th consecutive year, hitting 5,154, 7 percent higher than the 2006 total. Meanwhile, car fatalities fell by 8 percent and light truck fatalities fell by 3 percent, "pushing the overall death rate [for motor vehicle accidents] to a historic low," The New York Times reports. The share of motor vehicle deaths caused by motorcycle crashes has more than doubled since 1997, from 5 percent to 13 percent. Although advocates of helmet laws will be inclined to blame their repeal in several states for the rising motorcycle fatalities, the chief culprit recently seems to be higher gas prices, which have encouraged people to take advantage of motorcycles' vastly superior fuel efficiency:

Motorcycle ridership appears to be rising even as the total miles for all vehicles drops....The highway safety authorities say that about 75 percent more motorcycles are registered today than 10 years ago. They suspect each motorcycle is ridden more miles, but the National Highway Traffic Safety Administration says it does not have a reliable measurement of use.

The lack of such data makes it difficult to tell how much of an increase in fatalities following repeal of a helmet law results from less helmet wearing and how much results from more riding. The Times avers that "ridership has probably become more dangerous mile for mile," but without reliable information on miles ridden, it's impossible to know for sure. Assuming the Times is right, less helmet wearing is not the only explanation:  

Safety officials say many of the [newer] riders are middle-age or older men who rode when they were young, gave it up as they raised children and have recently gone back to the bike. "They think they still have the same reflexes," said James Port, the safety agency's deputy administrator.

Motorcycle riding is inherently dangerous. While wearing a helmet reduces the risk of certain injuries, research suggests the overall impact on fatalities is modest. The unimpressive numbers are one reason motorcyclists have been so successful at defending their right to decide what, if anything, to wear on their heads. "We are the only industrialized country in the world where there is an organized effort to weaken or repeal motorcycle helmet laws," complains Russ Rader of the Insurance Institute for Highway Safety. Is that a sign of backwardness or a point of pride?