Some legislators have squelched bills for higher speed limits, citing research published in 2009 by Lee S. Friedman, PhD; Donald Hedeker, PhD; Elihu D. Richter, MD, MPH.
The research is entitled “Long-term Effects of Repealing the National Maximum Speed Limit in the United States”. http://www.medscape.com/viewarticle/715218
The facts are simple: National Speed Prohibition was repealed effective November 28, 1995. In 1995, interstates had 4,836 deaths while US traffic deaths overall totaled 41,798.
By 2005, interstate deaths had climbed 21% to 5,874; while US traffic deaths were up 3% to 43,443.
Motivation enough for publication!
NOW THE REST OF THE STORY
By 2011, interstate traffic deaths had dropped to 4,112; total traffic deaths plunged to 32,367. Those figures are 15% and 25% lower than the counts in 1995, respectively. Compared to the peak 2005 figures — 30% and 23% lower respectively.
I’ve not even bothered accounting for increased travel, different speed limits (65, 70, 75), etc.
So was the 25% increase in interstate fatalities through 2005 due to higher speeds? Or was the subsequent 30% decrease through 2011 due to higher speeds?
Correlation isn’t causation; perhaps there’s no correlation with speed at all.
I imagine we’ll never see a follow-up study by Drs Friedman, Hedeker and Richter, eh?