Fatalities caused by motor vehicle accidents rose from 2004 to 2005. Since that time, U.S. car crash deaths have dropped steadily. Estimates from 2012 show that trend may have come to an end. According to the National Safety Council, car crashes claimed some 36,200 lives in 2012. That would represent a five percent increase over 2011. While no single factor can account for the change, the NSC report suggested that an increase in the total number of miles driven may explain an increase in traffic deaths.
Several factors may have contributed to the increase in miles driven. The winter of 2012 was relatively mild. Severe weather makes traffic deaths more likely for those on the roads, but it tends to depress the total number of fatalities as many people refrain from driving in challenging conditions. In addition, an improving economy may have contributed to an increase in traffic, particularly in commuter traffic as unemployment dropped.
Several states reported an increase in traffic deaths well above the national average. Many of those states were in the Northeast, where weather conditions were so mild that several states reported motorcycle crash deaths in December. The increase was more than ten percent in several of these states.
The NSC report did indicate that law enforcement efforts to combat speeding may have decreased in 2012. Budget constraints can lead local law enforcement to reduce efforts to catch speeders in order to maintain enforcement levels for more serious crimes. Speeding is cited as a contributing factor in roughly one-third of all traffic deaths.
Source: Los Angeles Times, "Crash-related deaths up for first time since 2005, report says," by David Undercoffler, 20 February 2013